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706 lines
27 KiB
Markdown
706 lines
27 KiB
Markdown
# Enhances miscellaneous security settings
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## Kernel hardening
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This section is inspired by the Kernel Self Protection Project (KSPP). It
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implements all recommended Linux kernel settings by the KSPP and many more.
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- https://kernsec.org/wiki/index.php/Kernel_Self_Protection_Project
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- https://kspp.github.io/Recommended_Settings
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### sysctl
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sysctl settings are configured via the `/usr/lib/sysctl.d/990-security-misc.conf`
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configuration file.
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Significant hardening is applied by default to a myriad of components within kernel
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space, user space, core dumps, and swap space.
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- Restrict access to kernel addresses through the use of kernel pointers regardless
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of user privileges.
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- Restrict access to the kernel logs to `CAP_SYSLOG` as they often contain
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sensitive information.
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- Prevent kernel information leaks in the console during boot.
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- Restrict eBPF access to `CAP_BPF` and enable associated JIT compiler hardening.
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- Restrict loading TTY line disciplines to `CAP_SYS_MODULE`.
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- Restrict the `userfaultfd()` syscall to `CAP_SYS_PTRACE`, which reduces the
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likelihood of use-after-free exploits.
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- Disable `kexec` as it can be used to replace the running kernel.
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- Entirely disable the SysRq key so that the Secure Attention Key (SAK)
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can no longer be utilized. See [documentation](https://www.kicksecure.com/wiki/SysRq).
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- Restrict user namespaces to `CAP_SYS_ADMIN` as they can lead to substantial
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privilege escalation.
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- Restrict kernel profiling and the performance events system to `CAP_PERFMON`.
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- Force the kernel to panic on "oopses" that can potentially indicate and thwart
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certain kernel exploitation attempts. Provide the option to reboot immediately
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on a kernel panic.
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- Randomize the addresses (ASLR) for mmap base, stack, VDSO pages, and heap.
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- Disable the use of legacy TIOCSTI operations which can be used to inject keypresses.
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- Disable asynchronous I/O as `io_uring` has been the source
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of numerous kernel exploits (when using Linux kernel version >= 6.6).
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- Restrict usage of `ptrace()` to only processes with `CAP_SYS_PTRACE` as it
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enables programs to inspect and modify other active processes. Provide the
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option to entirely disable the use of `ptrace()` for all processes.
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- Prevent hardlink and symlink TOCTOU races in world-writable directories.
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- Disallow unintentional writes to files in world-writable directories unless
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they are owned by the directory owner to mitigate some data spoofing attacks.
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- Increase the maximum number of memory map areas a process is able to utilize.
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- Disable core dump files and prevent their creation. If core dump files are
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enabled, they will be named based on `core.PID` instead of the default `core`.
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- Limit the copying of potentially sensitive content in memory to the swap device.
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Various networking components of the TCP/IP stack are hardened for IPv4/6.
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- Enable TCP SYN cookie protection to assist against SYN flood attacks.
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- Protect against TCP time-wait assassination hazards.
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- Enable reverse path filtering (source validation) of packets received
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from all interfaces to prevent IP spoofing.
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- Disable ICMP redirect acceptance and redirect sending messages to
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prevent man-in-the-middle attacks and minimize information disclosure. If
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ICMP redirect messages are permitted, only do so from approved gateways.
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- Ignore ICMP echo requests to prevent clock fingerprinting and Smurf attacks.
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- Ignore bogus ICMP error responses.
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- Disable source routing which allows users to redirect network traffic that
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can result in man-in-the-middle attacks.
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- Do not accept IPv6 router advertisements and solicitations.
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- Provide the option to disable SACK and DSACK as they have historically been
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a known vector for exploitation.
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- Disable TCP timestamps as they can allow detecting the system time.
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- Provide the option to log packets with impossible source or destination
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addresses to enable further inspection and analysis.
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- Provide the option to enable IPv6 Privacy Extensions.
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### mmap ASLR
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- The bits of entropy used for mmap ASLR are maxed out via
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`/usr/libexec/security-misc/mmap-rnd-bits` (set to the values of
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`CONFIG_ARCH_MMAP_RND_BITS_MAX` and `CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MAX`
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that the kernel was built with), therefore improving its effectiveness.
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### Boot parameters
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Mitigations for known CPU vulnerabilities are enabled in their strictest form
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and simultaneous multithreading (SMT) is disabled. See the
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`/etc/default/grub.d/40_cpu_mitigations.cfg` configuration file.
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Boot parameters relating to kernel hardening, DMA mitigations, and entropy
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generation are outlined in the `/etc/default/grub.d/40_kernel_hardening.cfg`
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configuration file.
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- Disable merging of slabs with similar size, which reduces the risk of
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triggering heap overflows and limits influencing slab cache layout.
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- Enable sanity checks and red zoning via slab debugging. This will implicitly
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disable kernel pointer hashing, leaking very sensitive information to root.
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- Enable memory zeroing at both allocation and free time, which mitigates some
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use-after-free vulnerabilities by erasing sensitive information in memory.
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- Enable the kernel page allocator to randomize free lists to limit some data
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exfiltration and ROP attacks, especially during the early boot process.
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- Enable kernel page table isolation to increase KASLR effectiveness and also
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mitigate the Meltdown CPU vulnerability.
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- Enable randomization of the kernel stack offset on syscall entries to harden
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against memory corruption attacks.
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- Disable vsyscalls as they are vulnerable to ROP attacks and have now been
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replaced by vDSO.
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- Restrict access to debugfs by not registering the file system since it can
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contain sensitive information.
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- Force kernel panics on "oopses" to potentially indicate and thwart certain
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kernel exploitation attempts.
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- Provide the option to modify machine check exception handler.
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- Enable the kernel Electric-Fence sampling-based memory safety error detector
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which can identify heap out-of-bounds access, use-after-free, and invalid-free errors.
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- Disable 32-bit vDSO mappings as they are a legacy compatibility feature.
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- Provide the option to use kCFI as the default CFI implementation since it may be
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slightly more resilient to attacks that are able to write arbitrary executables
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in memory (when using Linux kernel version >= 6.2).
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- Provide the option to disable support for all x86 processes and syscalls to reduce
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attack surface (when using Linux kernel version >= 6.7).
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- Enable strict IOMMU translation to protect against DMA attacks and disable
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the busmaster bit on all PCI bridges during the early boot process.
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- Do not credit the CPU or bootloader as entropy sources at boot in order to
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maximize the absolute quantity of entropy in the combined pool.
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- Obtain more entropy at boot from RAM as the runtime memory allocator is
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being initialized.
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- Provide the option to disable the entire IPv6 stack to reduce attack surface.
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Disallow sensitive kernel information leaks in the console during boot. See
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the `/etc/default/grub.d/41_quiet_boot.cfg` configuration file.
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### Kernel Modules
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#### Kernel Module Signature Verification
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Not yet implemented due to issues:
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- https://forums.whonix.org/t/enforce-kernel-module-software-signature-verification-module-signing-disallow-kernel-module-loading-by-default/7880/64
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- https://github.com/dell/dkms/issues/359
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See:
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- `/etc/default/grub.d/40_signed_modules.cfg`
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#### Disables the loading of new modules to the kernel after the fact
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Not yet implemented due to issues:
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- https://github.com/Kicksecure/security-misc/pull/152
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A systemd service dynamically sets the kernel parameter `modules_disabled` to 1,
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preventing new modules from being loaded. Since this isn't configured directly
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within systemctl, it does not break the loading of legitimate and necessary
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modules for the user, like drivers etc., given they are plugged in on startup.
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#### Blacklist and disable kernel modules
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Conntrack: Deactivates Netfilter's connection tracking helper module which
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increases kernel attack surface by enabling superfluous functionality such
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as IRC parsing in the kernel. See `/etc/modprobe.d/30_security-misc_conntrack.conf`.
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Certain kernel modules are blacklisted by default to reduce attack surface via
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`/etc/modprobe.d/30_security-misc_blacklist.conf`. Blacklisting prevents kernel
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modules from automatically starting.
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- CD-ROM/DVD: Blacklist modules required for CD-ROM/DVD devices.
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- Framebuffer Drivers: Blacklisted as they are well-known to be buggy, cause
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kernel panics, and are generally only used by legacy devices.
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- Miscellaneous: Blacklist an assortment of other modules to prevent them from
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automatically loading.
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Specific kernel modules are entirely disabled to reduce attack surface via
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`/etc/modprobe.d/30_security-misc_disable.conf`. Disabling prohibits kernel
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modules from starting. This approach should not be considered comprehensive;
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rather, it is a form of badness enumeration. Any potential candidates for future
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disabling should first be blacklisted for a suitable amount of time.
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- Optional - Bluetooth: Disabled to reduce attack surface.
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- Optional - CPU MSRs: Disabled as can be abused to write to arbitrary memory.
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- File Systems: Disable uncommon and legacy file systems.
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- FireWire (IEEE 1394): Disabled as they are often vulnerable to DMA attacks.
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- GPS: Disable GPS-related modules such as those required for Global Navigation
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Satellite Systems (GNSS).
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- Optional - Intel Management Engine (ME): Provides some disabling of the interface
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between the Intel ME and the OS. May lead to breakages in places such as security,
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power management, display, and DRM. See discussion: https://github.com/Kicksecure/security-misc/issues/239
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- Intel Platform Monitoring Technology Telemetry (PMT): Disable some functionality
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of the Intel PMT components.
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- Network File Systems: Disable uncommon and legacy network file systems.
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- Network Protocols: A wide array of uncommon and legacy network protocols and drivers
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are disabled.
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- Miscellaneous: Disable an assortment of other modules such as those required
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for amateur radio, floppy disks, and vivid.
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- Thunderbolt: Disabled as they are often vulnerable to DMA attacks.
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- Optional - USB Video Device Class: Disables the USB-based video streaming driver for
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devices like some webcams and digital camcorders.
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### Other
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- A systemd service clears the System.map file on boot as these contain kernel
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pointers. The file is completely overwritten with zeroes to ensure it cannot
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be recovered. See:
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`/etc/kernel/postinst.d/30_remove-system-map`
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`/lib/systemd/system/remove-system-map.service`
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`/usr/libexec/security-misc/remove-system.map`
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- Coredumps are disabled as they may contain important information such as
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encryption keys or passwords. See:
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`/etc/security/limits.d/30_security-misc.conf`
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`/etc/sysctl.d/30_security-misc.conf`
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`/lib/systemd/coredump.conf.d/30_security-misc.conf`
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- An initramfs hook sets the sysctl values in `/etc/sysctl.conf` and
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`/etc/sysctl.d` before init is executed so sysctl hardening is enabled as
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early as possible. This is implemented for `initramfs-tools` only because
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this is not needed for `dracut` as `dracut` does that by default, at
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least on `systemd` enabled systems. Not researched for non-`systemd` systems
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by the author of this part of the readme.
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## Network hardening
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Not yet implemented due to issues:
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- https://github.com/Kicksecure/security-misc/pull/145
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- https://github.com/Kicksecure/security-misc/issues/184
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- Unlike version 4, IPv6 addresses can provide information not only about the
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originating network but also the originating device. We prevent this from
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happening by enabling the respective privacy extensions for IPv6.
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- In addition, we deny the capability to track the originating device in the
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network at all, by using randomized MAC addresses per connection by
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default.
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See:
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- `/usr/lib/NetworkManager/conf.d/80_ipv6-privacy.conf`
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- `/usr/lib/NetworkManager/conf.d/80_randomize-mac.conf`
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- `/usr/lib/systemd/networkd.conf.d/80_ipv6-privacy-extensions.conf`
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## Bluetooth Hardening
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### Bluetooth Status: Enabled but Defaulted to Off
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- **Default Behavior**: Although Bluetooth capability is 'enabled' in the kernel,
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security-misc deviates from the usual behavior by starting with Bluetooth
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turned off at system start. This setting remains until the user explicitly opts
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to activate Bluetooth.
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- **User Control**: Users have the freedom to easily switch Bluetooth on and off
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in the usual way, exercising their own discretion. This can be done via the
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Bluetooth toggle through the usual way, that is either through GUI settings
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application or command line commands.
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- **Enhanced Privacy Settings**: We enforce more private defaults for Bluetooth
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connections. This includes the use of private addresses and strict timeout
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settings for discoverability and visibility.
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- **Security Considerations**: Despite these measures, it's important to note that
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Bluetooth technology, by its nature, may still be prone to exploits due to its
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history of security vulnerabilities. Thus, we recommend users to opt-out of
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using Bluetooth when possible.
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### Configuration Details
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- See configuration: `/etc/bluetooth/30_security-misc.conf`
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- For more information and discussion: [GitHub Pull Request](https://github.com/Kicksecure/security-misc/pull/145)
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### Understanding Bluetooth Terms
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- **Disabling Bluetooth**: This means the absence of the Bluetooth kernel module.
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When disabled, Bluetooth is non-existent in the system - it cannot be seen, set,
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configured, or interacted with in any way.
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- **Turning Bluetooth On/Off**: This refers to a software toggle. Normally, on
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Debian systems, Bluetooth is 'on' when the system boots up. It actively searches
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for known devices to auto-connect and may be discoverable or visible under certain
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conditions. Our default ensures that Bluetooth is off on startup. However, it
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remains 'enabled' in the kernel, meaning the kernel can use the Bluetooth protocol
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and has the necessary modules.
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### Quick Toggle Guide
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- **Turning Bluetooth On**: Simply click the Bluetooth button in the settings
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application or on the tray, and switch the toggle. It's a straightforward action
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that can be completed in less than a second.
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- **Turning Bluetooth Off**: Follow the same procedure as turning it on but switch
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the toggle to the off position.
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## Entropy collection improvements
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- The `jitterentropy_rng` kernel module is loaded as early as possible during
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boot to gather more entropy via the
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`/usr/lib/modules-load.d/30_security-misc.conf` configuration file.
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- Distrusts the CPU for initial entropy at boot as it is not possible to
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audit, may contain weaknesses or a backdoor. Similarly, do not credit the
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bootloader seed for initial entropy. For references, see:
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`/etc/default/grub.d/40_kernel_hardening.cfg`
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- Gathers more entropy during boot if using the linux-hardened kernel patch.
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## Restrictive mount options
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A systemd service is triggered on boot to remount all sensitive partitions and
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directories with significantly more secure hardened mount options. Since this
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would require manual tuning for a given specific system, we handle it by
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creating a very solid configuration file for that very system on package
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installation.
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Not enabled by default yet. In development. Help welcome.
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- https://www.kicksecure.com/wiki/Dev/remount-secure
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- https://github.com/Kicksecure/security-misc/issues/157
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- https://forums.whonix.org/t/re-mount-home-and-other-with-noexec-and-nosuid-among-other-useful-mount-options-for-better-security/
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## Root access restrictions
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- `su` is restricted to only users within the group `sudo` which prevents
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users from using `su` to gain root access or to switch user accounts -
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`/usr/share/pam-configs/wheel-security-misc` (which results in a change in
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file `/etc/pam.d/common-auth`).
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- Add user `root` to group `sudo`. This is required due to the above
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restriction so that logging in from a virtual console is still possible -
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`debian/security-misc.postinst`
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- Abort login for users with locked passwords -
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`/usr/libexec/security-misc/pam-abort-on-locked-password`.
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- Logging into the root account from a virtual, serial, or other console is
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prevented by shipping an existing and empty `/etc/securetty` file (deletion
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of `/etc/securetty` has a different effect).
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This package does not yet automatically lock the root account password. It is
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not clear if this would be sane in such a package, although it is recommended to
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lock and expire the root account.
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In new Kicksecure builds, the root account will be locked by package
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dist-base-files.
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See:
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- https://www.kicksecure.com/wiki/Root
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- https://www.kicksecure.com/wiki/Dev/Permissions
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- https://forums.whonix.org/t/restrict-root-access/7658
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However, a locked root password will break rescue and emergency shell.
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Therefore, this package enables passwordless rescue and emergency shell. This is
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the same solution that Debian will likely adopt for the Debian installer:
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https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=802211
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See:
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- `/etc/systemd/system/emergency.service.d/override.conf`
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- `/etc/systemd/system/rescue.service.d/override.conf`
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Adverse security effects can be prevented by setting up BIOS password
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protection, GRUB password protection, and/or full disk encryption.
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## Console lockdown
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This uses pam_access to allow members of group `console` to use the console but
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restrict everyone else (except members of group `console-unrestricted`) from
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using the console with ancient, unpopular login methods such as `/bin/login` over
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networks as this might be exploitable. (CVE-2001-0797)
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This is not enabled by default in this package since this package does not know
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which users should be added to group 'console' and thus, would break console access.
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See:
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- `/usr/share/pam-configs/console-lockdown-security-misc`
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- `/etc/security/access-security-misc.conf`
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## Brute force attack protection
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User accounts are locked after 50 failed login attempts using `pam_faillock`.
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Informational output during Linux PAM:
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- Show failed and remaining password attempts.
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- Document unlock procedure if Linux user account got locked.
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- Point out that there is no password feedback for `su`.
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- Explain locked root account if locked.
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See:
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- `/usr/share/pam-configs/tally2-security-misc`
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- `/usr/libexec/security-misc/pam-info`
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- `/usr/libexec/security-misc/pam-abort-on-locked-password`
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## Access rights restrictions
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### Strong user account separation
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#### Permission Lockdown
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Read, write, and execute access for "others" are removed during package
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installation, upgrade, or PAM `mkhomedir` for all users who have home folders in
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`/home` by running, for example:
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```
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chmod o-rwx /home/user
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```
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This will be done only once per folder in `/home` so users who wish to relax
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file permissions are free to do so. This is to protect files in a home folder
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that were previously created with lax file permissions prior to the installation
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of this package.
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See:
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- `debian/security-misc.postinst`
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- `/usr/libexec/security-misc/permission-lockdown`
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- `/usr/share/pam-configs/mkhomedir-security-misc`
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#### umask
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Default `umask` is set to `027` for files created by non-root users such as
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user `user`. Broken. Disabled. See:
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* https://github.com/Kicksecure/security-misc/issues/184
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This is done using the PAM module `pam_mkhomedir.so umask=027`.
|
|
|
|
This means files created by non-root users cannot be read by other non-root
|
|
users by default. While Permission Lockdown already protects the `/home` folder,
|
|
this protects other folders such as `/tmp`.
|
|
|
|
`group` read permissions are not removed. This is unnecessary due to Debian's
|
|
use of User Private Groups (UPGs). See also:
|
|
https://wiki.debian.org/UserPrivateGroups
|
|
|
|
Default `umask` is unchanged for root because then configuration files created
|
|
in `/etc` by the system administrator would be unreadable by "others" and break
|
|
applications. Examples include `/etc/firefox-esr` and `/etc/thunderbird`.
|
|
|
|
See:
|
|
|
|
- `/usr/share/pam-configs/umask-security-misc`
|
|
|
|
### SUID / SGID removal and permission hardening
|
|
|
|
#### SUID / SGID removal
|
|
|
|
A systemd service removes SUID / SGID bits from non-essential binaries as these
|
|
are often used in privilege escalation attacks.
|
|
|
|
#### File permission hardening
|
|
|
|
Various file permissions are reset with more secure and hardened defaults. These
|
|
include but are not limited to:
|
|
|
|
- Limiting `/home` and `/root` to the root only.
|
|
- Limiting crontab to root as well as all the configuration files for cron.
|
|
- Limiting the configuration for cups and ssh.
|
|
- Protecting the information of sudoers from others.
|
|
- Protecting various system-relevant files and modules.
|
|
|
|
##### permission-hardener
|
|
|
|
`permission-hardener` removes SUID / SGID bits from non-essential binaries as
|
|
these are often used in privilege escalation attacks. It is enabled by default
|
|
and applied at security-misc package installation and upgrade time.
|
|
|
|
There is also an optional systemd unit which does the same at boot time that
|
|
can be enabled by running `systemctl enable permission-hardener.service` as
|
|
root. The hardening at boot time is not the default because this slows down
|
|
the boot process too much.
|
|
|
|
See:
|
|
|
|
* `/usr/bin/permission-hardener`
|
|
* `debian/security-misc.postinst`
|
|
* `/lib/systemd/system/permission-hardener.service`
|
|
* `/etc/permission-hardener.d`
|
|
* https://forums.whonix.org/t/disable-suid-binaries/7706
|
|
* https://www.kicksecure.com/wiki/SUID_Disabler_and_Permission_Hardener
|
|
|
|
### Access rights relaxations
|
|
|
|
This is not enabled yet because hidepid is not enabled by default.
|
|
|
|
Calls to `pkexec` are redirected to `lxqt-sudo` because `pkexec` is
|
|
incompatible with `hidepid=2`.
|
|
|
|
See:
|
|
|
|
* `/usr/bin/pkexec.security-misc`
|
|
* https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=860040
|
|
* https://forums.whonix.org/t/cannot-use-pkexec/8129
|
|
|
|
## Application-specific hardening
|
|
|
|
- Enables "`apt-get --error-on=any`" which makes apt exit non-zero for
|
|
transient failures. - `/etc/apt/apt.conf.d/40error-on-any`.
|
|
- Enables APT seccomp-BPF sandboxing - `/etc/apt/apt.conf.d/40sandbox`.
|
|
- Deactivates previews in Dolphin.
|
|
- Deactivates previews in Nautilus -
|
|
`/usr/share/glib-2.0/schemas/30_security-misc.gschema.override`.
|
|
- Deactivates thumbnails in Thunar.
|
|
- Rationale: lower attack surface when using the file manager
|
|
- https://forums.whonix.org/t/disable-preview-in-file-manager-by-default/18904
|
|
- Thunderbird is hardened with the following options:
|
|
- Displays domain names in punycode to prevent IDN homograph attacks (a
|
|
form of phishing).
|
|
- Strips email client information from sent email headers.
|
|
- Strips user time information from sent email headers by replacing the
|
|
originating time zone with UTC and rounding the timestamp to the nearest
|
|
minute.
|
|
- Disables scripting when viewing PDF files.
|
|
- Disables implicit outgoing connections.
|
|
- Disables all and any kind of telemetry.
|
|
- Security and privacy enhancements for gnupg's config file
|
|
`/etc/skel/.gnupg/gpg.conf`. See also:
|
|
- https://raw.github.com/ioerror/torbirdy/master/gpg.conf
|
|
- https://github.com/ioerror/torbirdy/pull/11
|
|
|
|
### Project scope of application-specific hardening
|
|
|
|
Added in December 2023.
|
|
|
|
Before sending pull requests to harden arbitrary applications, please note the
|
|
scope of security-misc is limited to default installed applications in
|
|
Kicksecure and Whonix. This includes:
|
|
|
|
- Thunderbird, VLC Media Player, KeePassXC
|
|
- Debian Specific System Components (APT, DPKG)
|
|
- System Services (NetworkManager IPv6 privacy options, MAC address
|
|
randomization)
|
|
- Actually used development utilities such as `git`.
|
|
|
|
It will not be possible to review and merge "1500" settings profiles for
|
|
arbitrary applications outside of this context.
|
|
|
|
The main objective of security-misc is to harden Kicksecure and its derivatives,
|
|
such as Whonix, by implementing robust security settings. It's designed to be
|
|
compatible with Debian, reflecting a commitment to clean implementation and
|
|
sound design principles. However, it's important to note that security-misc is a
|
|
component of Kicksecure, not a substitute for it. The intention isn't to
|
|
recreate Kicksecure within security-misc. Instead, specific security
|
|
enhancements, like recommending a curated list of security-focused
|
|
default packages (e.g., `libpam-tmpdir`), should be integrated directly into
|
|
those appropriate areas of Kicksecure (e.g. `kicksecure-meta-packages`).
|
|
|
|
Discussion: https://github.com/Kicksecure/security-misc/issues/154
|
|
|
|
### Development philosophy
|
|
|
|
Added in December 2023.
|
|
|
|
Maintainability is a key priority \[1\]. Before modifying settings in the
|
|
downstream security-misc, it's essential to first engage with upstream
|
|
developers to propose these changes as defaults. This step should only be
|
|
bypassed if there's a clear, prior indication from upstream that such changes
|
|
won't be accepted. Additionally, before implementing any workarounds, consulting
|
|
with upstream is necessary to avoid future unmaintainable complexity.
|
|
|
|
If debugging features are disabled, pull requests won't be merged until there is
|
|
a corresponding pull request for the debug-misc package to re-enable these. This
|
|
is to avoid configuring the system into a corner where it can no longer be
|
|
debugged.
|
|
|
|
\[1\] https://www.kicksecure.com/wiki/Dev/maintainability
|
|
|
|
## Opt-in hardening
|
|
|
|
Some hardening is opt-in as it causes too much breakage to be enabled by
|
|
default.
|
|
|
|
- An optional systemd service mounts `/proc` with `hidepid=2` at boot to
|
|
prevent users from seeing another user's processes. This is disabled by
|
|
default because it is incompatible with `pkexec`. It can be enabled by
|
|
executing `systemctl enable proc-hidepid.service` as root.
|
|
|
|
- A systemd service restricts `/proc/cpuinfo`, `/proc/bus`, `/proc/scsi`, and
|
|
`/sys` to the root user. This hides a lot of hardware identifiers from
|
|
unprivileged users and increases security as `/sys` exposes a lot of
|
|
information that shouldn't be accessible to unprivileged users. As this will
|
|
break many things, it is disabled by default and can optionally be enabled
|
|
by executing `systemctl enable hide-hardware-info.service` as root.
|
|
|
|
## Miscellaneous
|
|
|
|
- Hardened malloc compatibility for haveged workaround
|
|
`/lib/systemd/system/haveged.service.d/30_security-misc.conf`
|
|
|
|
- Set `dracut` `reproducible=yes` setting
|
|
|
|
## Legal
|
|
|
|
`/usr/lib/issue.d/20_security-misc.issue`
|
|
|
|
https://github.com/Kicksecure/security-misc/pull/167
|
|
|
|
## Related
|
|
|
|
- Linux Kernel Runtime Guard (LKRG)
|
|
- tirdad - TCP ISN CPU Information Leak Protection.
|
|
- Kicksecure (TM) - a security-hardened Linux Distribution
|
|
- And more.
|
|
- https://www.kicksecure.com/wiki/Linux_Kernel_Runtime_Guard_LKRG
|
|
- https://github.com/Kicksecure/tirdad
|
|
- https://www.kicksecure.com
|
|
- https://github.com/Kicksecure
|
|
|
|
## Discussion
|
|
|
|
Happening primarily in forums.
|
|
|
|
https://forums.whonix.org/t/kernel-hardening/7296
|
|
|
|
## How to install `security-misc`
|
|
|
|
See https://www.kicksecure.com/wiki/Security-misc#install
|
|
|
|
## How to Build deb Package from Source Code
|
|
|
|
Can be build using standard Debian package build tools such as:
|
|
|
|
dpkg-buildpackage -b
|
|
|
|
See instructions. (Replace `generic-package` with the actual name of this
|
|
package `security-misc`.)
|
|
|
|
- **A)**
|
|
[easy](https://www.kicksecure.com/wiki/Dev/Build_Documentation/generic-package/easy),
|
|
*OR*
|
|
- **B)** [including verifying software
|
|
signatures](https://www.kicksecure.com/wiki/Dev/Build_Documentation/generic-package)
|
|
|
|
## Contact
|
|
|
|
- [Free Forum Support](https://forums.kicksecure.com)
|
|
- [Professional Support](https://www.kicksecure.com/wiki/Professional_Support)
|
|
|
|
## Donate
|
|
|
|
`security-misc` requires [donations](https://www.kicksecure.com/wiki/Donate) to
|
|
stay alive!
|