CVE-2024-50254
📋 TL;DR
This CVE describes a memory leak vulnerability in the Linux kernel's BPF subsystem where bpf_iter_bits_destroy() fails to properly free dynamically allocated memory. The vulnerability affects Linux systems with BPF enabled and could lead to kernel memory exhaustion over time. Attackers with local access could potentially exploit this to degrade system performance or cause denial of service.
💻 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 →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
Sustained exploitation could lead to kernel memory exhaustion, causing system instability, crashes, or denial of service conditions affecting all processes.
Likely Case
Gradual memory leak leading to performance degradation over time, potentially requiring system reboots to clear accumulated memory.
If Mitigated
Minimal impact with proper monitoring and timely patching, though some memory pressure may occur before detection.
🎯 Exploit Status
Exploitation requires local access and ability to trigger BPF iterator operations. The vulnerability is a memory leak rather than a privilege escalation or remote code execution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in kernel commits 101ccfbabf4738041273ce64e2b116cf440dea13 and 9cee266fafaf79fd465314546f637f9a3c215830
Vendor Advisory: https://git.kernel.org/stable/c/101ccfbabf4738041273ce64e2b116cf440dea13
Restart Required: Yes
Instructions:
1. Update to a kernel version containing the fix commits. 2. Check with your Linux distribution for specific patched kernel packages. 3. Reboot the system to load the new kernel.
🔧 Temporary Workarounds
Disable BPF subsystem
linuxDisable the BPF subsystem to prevent exploitation of this vulnerability
echo 'kernel.bpf_disabled=1' >> /etc/sysctl.conf
sysctl -p
Restrict BPF usage
linuxUse kernel lockdown mode or BPF restrictions to limit who can use BPF features
echo 'kernel.kexec_load_disabled=1' >> /etc/sysctl.conf
sysctl -p
🧯 If You Can't Patch
- Implement strict access controls to limit local user privileges
- Monitor system memory usage and kernel logs for signs of memory leaks
🔍 How to Verify
Check if Vulnerable:
Check kernel version and verify if it contains the vulnerable bpf_iter_bits_destroy() implementation. Use 'uname -r' and compare with distribution security advisories.Check Version:
uname -rVerify Fix Applied:
Verify kernel version contains the fix commits (101ccfbabf4738041273ce64e2b116cf440dea13 or 9cee266fafaf79fd465314546f637f9a3c215830) using 'cat /proc/version' or distribution package manager.📡 Detection & Monitoring
Log Indicators:
- Kernel oom-killer messages
- Increased memory pressure warnings in dmesg
- kmemleak reports of unreferenced objects
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="kernel" AND ("oom-killer" OR "memory pressure" OR "kmemleak")