CVE-2024-42068
📋 TL;DR
This Linux kernel vulnerability in the BPF subsystem occurs when the bpf_prog_lock_ro() function fails to properly handle errors from set_memory_ro(), potentially leaving memory pages writable when they should be read-only. This affects systems running vulnerable Linux kernel versions with BPF enabled. Attackers could potentially modify supposedly protected memory regions.
💻 Affected Systems
- Linux Kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
An attacker could modify read-only BPF program memory to execute arbitrary code with kernel privileges, leading to full system compromise.
Likely Case
Local privilege escalation where an authenticated user gains kernel-level access to modify system memory.
If Mitigated
With proper kernel hardening and BPF restrictions, impact is limited to denial of service or information disclosure.
🎯 Exploit Status
Exploitation requires local access and BPF privileges. No public exploits known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Multiple stable kernel versions with commits: 05412471beba, 7d2cc63eca0c, a359696856ca, e4f602e3ff74
Vendor Advisory: https://git.kernel.org/stable/c/05412471beba313ecded95aa17b25fe84bb2551a
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution vendor. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable BPF subsystem
linuxDisable BPF functionality to prevent exploitation
echo 0 > /proc/sys/kernel/unprivileged_bpf_disabled
Remove CAP_BPF from non-privileged users
Restrict BPF capabilities
linuxLimit which users can load BPF programs
sysctl -w kernel.unprivileged_bpf_disabled=1
🧯 If You Can't Patch
- Restrict BPF usage to trusted administrators only
- Implement strict access controls and monitor for unusual BPF program loading
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched versions from kernel.org stable treesCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes one of the fix commits: 05412471beba, 7d2cc63eca0c, a359696856ca, or e4f602e3ff74📡 Detection & Monitoring
Log Indicators:
- Failed BPF program loads
- Kernel oops or warnings related to memory protection
Network Indicators:
- None - local exploit only
SIEM Query:
Process monitoring for bpf() system calls from non-privileged users🔗 References
- https://git.kernel.org/stable/c/05412471beba313ecded95aa17b25fe84bb2551a
- https://git.kernel.org/stable/c/7d2cc63eca0c993c99d18893214abf8f85d566d8
- https://git.kernel.org/stable/c/a359696856ca9409fb97655c5a8ef0f549cb6e03
- https://git.kernel.org/stable/c/e4f602e3ff749ba770bf8ff10196e18358de6720
- https://git.kernel.org/stable/c/05412471beba313ecded95aa17b25fe84bb2551a
- https://git.kernel.org/stable/c/7d2cc63eca0c993c99d18893214abf8f85d566d8
- https://git.kernel.org/stable/c/a359696856ca9409fb97655c5a8ef0f549cb6e03
- https://git.kernel.org/stable/c/e3540e5a7054d6daaf9a1415a48aacb092112a89
- https://git.kernel.org/stable/c/e4f602e3ff749ba770bf8ff10196e18358de6720
- https://git.kernel.org/stable/c/fdd411af8178edc6b7bf260f8fa4fba1bedd0a6d
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
