CVE-2024-43910
📋 TL;DR
A vulnerability in the Linux kernel's BPF subsystem allows attackers to pass modified CONST_PTR_TO_DYNPTR arguments to global functions, potentially leading to out-of-bounds memory accesses. This can cause kernel crashes, system instability, or potentially be leveraged for privilege escalation. Systems running vulnerable Linux kernel versions with BPF enabled are affected.
💻 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
Kernel panic leading to denial of service, potential privilege escalation to root, or arbitrary code execution in kernel context.
Likely Case
Kernel crash or system instability causing denial of service, potentially leading to system reboots.
If Mitigated
Minimal impact if BPF is disabled or systems are properly patched.
🎯 Exploit Status
Exploitation requires ability to load and execute BPF programs, which typically requires CAP_BPF or root privileges. The vulnerability was discovered through kernel testing.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits 13663a7c644bf1dedaf461d07252db5d76c8759a and ec2b9a5e11e51fea1bb04c1e7e471952e887e874
Vendor Advisory: https://git.kernel.org/stable/c/13663a7c644bf1dedaf461d07252db5d76c8759a
Restart Required: Yes
Instructions:
1. Update to a kernel version containing the fix commits. 2. Check your distribution's security advisories for specific patched versions. 3. Reboot the system after kernel update.
🔧 Temporary Workarounds
Disable BPF subsystem
linuxDisable the BPF subsystem to prevent exploitation
echo 0 > /proc/sys/kernel/unprivileged_bpf_disabled
Remove BPF-related kernel modules if possible
Restrict BPF capabilities
linuxLimit BPF program loading to privileged users only
sysctl -w kernel.unprivileged_bpf_disabled=1
🧯 If You Can't Patch
- Implement strict access controls to prevent unauthorized users from loading BPF programs
- Monitor system logs for kernel panics or KASAN reports related to BPF operations
🔍 How to Verify
Check if Vulnerable:
Check kernel version and verify if it contains the fix commits. Run: uname -r and compare with your distribution's security advisories.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated to a version containing the fix commits. Check /proc/version or use package manager to verify kernel package version.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- KASAN reports mentioning bpf_dynptr_data or slab-out-of-bounds
- System crash/reboot logs
Network Indicators:
- None - this is a local kernel vulnerability
SIEM Query:
Search for kernel logs containing 'KASAN: slab-out-of-bounds', 'bpf_dynptr_data', or unexpected system reboots