CVE-2024-26619
📋 TL;DR
This CVE describes a use-after-free vulnerability in the Linux kernel's RISC-V module loading code. The vulnerability occurs when kernel memory is freed in the wrong order, potentially allowing attackers to execute arbitrary code or crash the system. It affects Linux systems running on RISC-V architecture with vulnerable kernel versions.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation to root, kernel panic causing system crash, or arbitrary code execution in kernel context leading to complete system compromise.
Likely Case
Kernel panic leading to denial of service (system crash) when malicious modules are loaded.
If Mitigated
No impact if proper kernel hardening and module signing are enforced, preventing unauthorized module loading.
🎯 Exploit Status
Requires local access and ability to load kernel modules. Exploitation would require crafting malicious kernel modules to trigger the use-after-free condition.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees via the provided git commits
Vendor Advisory: https://git.kernel.org/stable/c/2fa79badf4bfeffda6b5032cf62b828486ec9a99
Restart Required: Yes
Instructions:
1. Update to a patched kernel version from your distribution vendor. 2. For custom kernels, apply commits 2fa79badf4bfeffda6b5032cf62b828486ec9a99 and 78996eee79ebdfe8b6f0e54cb6dcc792d5129291. 3. Rebuild and install the kernel. 4. Reboot the system.
🔧 Temporary Workarounds
Restrict module loading
linuxPrevent unauthorized kernel module loading to block exploitation vectors
echo 1 > /proc/sys/kernel/modules_disabled
sysctl -w kernel.modules_disabled=1
Enable module signing enforcement
linuxRequire signed modules to prevent loading of untrusted modules
echo 1 > /sys/module/module/parameters/sig_enforce
Add 'module.sig_enforce=1' to kernel command line
🧯 If You Can't Patch
- Implement strict access controls to prevent unauthorized users from loading kernel modules
- Monitor for suspicious module loading activity and kernel crashes
🔍 How to Verify
Check if Vulnerable:
Check kernel version and architecture: uname -r and uname -m. If running RISC-V and kernel version is before the fix commits, system may be vulnerable.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and includes the fix commits. Check with: grep -q '2fa79badf4bfeffda6b5032cf62b828486ec9a99\|78996eee79ebdfe8b6f0e54cb6dcc792d5129291' /proc/version📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Failed module loading attempts
- Use-after-free kernel warnings in dmesg
Network Indicators:
- None - local exploitation only
SIEM Query:
source="kernel" AND ("use-after-free" OR "kernel panic" OR "BUG: kernel NULL pointer dereference")