CVE-2024-56720
📋 TL;DR
This CVE addresses multiple bugs in the Linux kernel's BPF subsystem, specifically in the bpf_msg_pop_data function used for socket map operations. The vulnerabilities could allow local attackers to cause kernel crashes or potentially achieve privilege escalation by exploiting memory management errors. Systems running affected Linux kernel versions with BPF enabled are at risk.
💻 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 →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 leading to full system compromise or kernel panic causing denial of service.
Likely Case
Kernel crash (denial of service) or memory corruption leading to system instability.
If Mitigated
Minimal impact if BPF is disabled or proper access controls restrict BPF usage to privileged users only.
🎯 Exploit Status
Exploitation requires local access and BPF program execution capabilities. The bugs involve memory management logic errors that could be leveraged by crafted BPF programs.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check kernel commit hashes: 275a9f3ef8fabb0cb282a62b9e164dedba7284c5, 5d609ba262475db450ba69b8e8a557bd768ac07a, 785180bed9879680d8e5c5e1b54c8ae8d948f4c8, 98c7ea7d11f2588e8197db042e0291e4ac8f8346, d26d977633d1d0b8bf9407278189bd0a8d973323
Vendor Advisory: https://git.kernel.org/stable/c/
Restart Required: Yes
Instructions:
1. Identify your Linux kernel version. 2. Check if patches are available for your distribution. 3. Update kernel package via package manager (apt/yum/dnf). 4. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable BPF subsystem
linuxPrevents exploitation by disabling the vulnerable BPF functionality.
echo 1 > /proc/sys/kernel/unprivileged_bpf_disabled
sysctl -w kernel.unprivileged_bpf_disabled=1
Restrict BPF capabilities
linuxLimit BPF usage to privileged users only via capability restrictions.
setcap -r /usr/bin/bpftool
configure system to require CAP_BPF or CAP_SYS_ADMIN for BPF operations
🧯 If You Can't Patch
- Implement strict access controls to prevent unprivileged users from loading BPF programs.
- Monitor system logs for kernel panics or BPF-related errors and implement intrusion detection.
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched versions in kernel git commits. Examine if BPF is enabled and accessible.Check Version:
uname -rVerify Fix Applied:
Verify kernel version after update matches patched version. Test BPF functionality to ensure stability.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- BPF-related error logs in dmesg or syslog
- Memory corruption warnings
Network Indicators:
- Not applicable - local exploitation only
SIEM Query:
source="kernel" AND ("panic" OR "BPF" OR "sockmap" OR "bpf_msg_pop_data")🔗 References
- https://git.kernel.org/stable/c/275a9f3ef8fabb0cb282a62b9e164dedba7284c5
- https://git.kernel.org/stable/c/5d609ba262475db450ba69b8e8a557bd768ac07a
- https://git.kernel.org/stable/c/785180bed9879680d8e5c5e1b54c8ae8d948f4c8
- https://git.kernel.org/stable/c/98c7ea7d11f2588e8197db042e0291e4ac8f8346
- https://git.kernel.org/stable/c/d26d977633d1d0b8bf9407278189bd0a8d973323
- https://git.kernel.org/stable/c/d3f5763b3062514a234114e97bbde74d8d702449
- https://git.kernel.org/stable/c/e1f54c61c4c9a5244eb8159dce60d248f7d97b32
- https://git.kernel.org/stable/c/f58d3aa457e77a3d9b3df2ab081dcf9950f6029f
- https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html
- https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html
