CVE-2024-26842
📋 TL;DR
This CVE describes an integer overflow vulnerability in the Linux kernel's UFS (Universal Flash Storage) driver. When task_tag values exceed 31 in MCQ mode, a 32-bit shift operation causes an out-of-bounds error that can crash the kernel. This affects systems using UFS storage with Linux kernel versions containing the vulnerable code.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash and denial of service, potentially causing data corruption or loss if storage operations are interrupted.
Likely Case
System crash or kernel panic when UFS storage operations trigger the specific condition with task_tag >= 32 in MCQ mode.
If Mitigated
No impact if the vulnerable code path is not triggered or if systems don't use UFS storage in MCQ mode.
🎯 Exploit Status
Exploitation requires triggering specific UFS storage operations with task_tag >= 32 in MCQ mode. This appears to be a reliability bug rather than a security vulnerability with arbitrary code execution potential.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions with commits 7ac9e18f5d66087cd22751c5c5bf0090eb0038fe, a992425d18e5f7c48931121993c6c69426f2a8fb, or b513d30d59bb383a6a5d6b533afcab2cee99a8f8
Vendor Advisory: https://git.kernel.org/stable/c/7ac9e18f5d66087cd22751c5c5bf0090eb0038fe
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable UFS MCQ mode
linuxPrevent the vulnerable code path by disabling Multiple Command Queue mode for UFS storage
echo 0 > /sys/class/ufs/ufs*/mcq_enable
🧯 If You Can't Patch
- Monitor system logs for UFS-related crashes or BRK exceptions
- Consider disabling UFS storage if not essential for system operation
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if UFS storage is present: lsblk -d | grep ufs && uname -rCheck Version:
uname -rVerify Fix Applied:
Verify kernel version contains fix commits: uname -r and check kernel source or changelog for the specific commits📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages mentioning ufshcd_clear_cmd
- BRK handler exceptions
- UFS error messages in dmesg
Network Indicators:
- None - this is a local storage driver issue
SIEM Query:
source="kernel" AND ("ufshcd_clear_cmd" OR "BRK handler" OR "UFS error")🔗 References
- https://git.kernel.org/stable/c/7ac9e18f5d66087cd22751c5c5bf0090eb0038fe
- https://git.kernel.org/stable/c/a992425d18e5f7c48931121993c6c69426f2a8fb
- https://git.kernel.org/stable/c/b513d30d59bb383a6a5d6b533afcab2cee99a8f8
- https://git.kernel.org/stable/c/7ac9e18f5d66087cd22751c5c5bf0090eb0038fe
- https://git.kernel.org/stable/c/a992425d18e5f7c48931121993c6c69426f2a8fb
- https://git.kernel.org/stable/c/b513d30d59bb383a6a5d6b533afcab2cee99a8f8
