CVE-2024-26791
📋 TL;DR
This CVE-2024-26791 is an out-of-bounds read vulnerability in the Linux kernel's Btrfs filesystem device replace functionality. Attackers could potentially read kernel memory beyond allocated buffers by passing improperly terminated device names, which could lead to information disclosure or system crashes. This affects Linux systems using Btrfs filesystem with device replacement capabilities.
💻 Affected Systems
- Linux kernel with Btrfs support
📦 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 →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
Kernel memory information disclosure leading to privilege escalation or system crash/DoS through kernel panic.
Likely Case
System crash or denial of service through kernel panic when processing malformed device names.
If Mitigated
Minimal impact with proper input validation and kernel hardening features enabled.
🎯 Exploit Status
Requires ability to trigger device replace operations with malformed device names, typically requiring local access or specific privileges.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in Linux kernel stable releases containing commits: 11d7a2e429c02d51e2dc90713823ea8b8d3d3a84, 2886fe308a83968dde252302884a1e63351cf16d, 343eecb4ff49a7b1cc1dfe86958a805cf2341cfb, 9845664b9ee47ce7ee7ea93caf47d39a9d4552c4, ab2d68655d0f04650bef09fee948ff80597c5fb9
Vendor Advisory: https://git.kernel.org/stable/c/11d7a2e429c02d51e2dc90713823ea8b8d3d3a84
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Check distribution-specific security advisories. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable Btrfs device replace
linuxPrevent device replace operations if not needed
# No direct command - avoid using 'btrfs replace' commands
Restrict device management privileges
linuxLimit who can perform device operations on Btrfs filesystems
# Use sudoers or capabilities to restrict btrfs command usage
🧯 If You Can't Patch
- Restrict access to users who can execute btrfs device management commands
- Implement strict input validation for any applications that interface with Btrfs device operations
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if Btrfs is in use: uname -r && lsmod | grep btrfsCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits or check with distribution's security advisory📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Btrfs device replace operation failures
- System crash dumps
Network Indicators:
- None - local vulnerability
SIEM Query:
Search for: kernel panic OR oops AND btrfs OR device_replace🔗 References
- https://git.kernel.org/stable/c/11d7a2e429c02d51e2dc90713823ea8b8d3d3a84
- https://git.kernel.org/stable/c/2886fe308a83968dde252302884a1e63351cf16d
- https://git.kernel.org/stable/c/343eecb4ff49a7b1cc1dfe86958a805cf2341cfb
- https://git.kernel.org/stable/c/9845664b9ee47ce7ee7ea93caf47d39a9d4552c4
- https://git.kernel.org/stable/c/ab2d68655d0f04650bef09fee948ff80597c5fb9
- https://git.kernel.org/stable/c/b1690ced4d2d8b28868811fb81cd33eee5aefee1
- https://git.kernel.org/stable/c/c6652e20d7d783d060fe5f987eac7b5cabe31311
- https://git.kernel.org/stable/c/f590040ce2b712177306b03c2a63b16f7d48d3c8
- https://git.kernel.org/stable/c/11d7a2e429c02d51e2dc90713823ea8b8d3d3a84
- https://git.kernel.org/stable/c/2886fe308a83968dde252302884a1e63351cf16d
- https://git.kernel.org/stable/c/343eecb4ff49a7b1cc1dfe86958a805cf2341cfb
- https://git.kernel.org/stable/c/9845664b9ee47ce7ee7ea93caf47d39a9d4552c4
- https://git.kernel.org/stable/c/ab2d68655d0f04650bef09fee948ff80597c5fb9
- https://git.kernel.org/stable/c/b1690ced4d2d8b28868811fb81cd33eee5aefee1
- https://git.kernel.org/stable/c/c6652e20d7d783d060fe5f987eac7b5cabe31311
- https://git.kernel.org/stable/c/f590040ce2b712177306b03c2a63b16f7d48d3c8
- https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html
- https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html
