CVE-2023-53348
📋 TL;DR
A race condition in the Linux kernel's Btrfs filesystem causes a deadlock when transaction abort occurs during block group relocation with scrub paused. This vulnerability can cause system hangs and denial of service. Systems using Btrfs filesystem with scrub and relocation features are affected.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Complete system hang requiring hard reboot, potential data corruption if filesystem operations are interrupted during critical transactions.
Likely Case
System becomes unresponsive during Btrfs operations, requiring manual intervention to restore functionality.
If Mitigated
Temporary service interruption during Btrfs maintenance operations with automatic recovery after timeout.
🎯 Exploit Status
Exploitation requires triggering specific Btrfs operations (scrub pause + relocation + transaction abort). Likely requires local access or ability to initiate Btrfs maintenance operations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel versions containing the fix commits
Vendor Advisory: https://git.kernel.org/stable/c/10a5831b193390b77705fc174a309476c23ba64a
Restart Required: No
Instructions:
1. Update Linux kernel to version containing fix commits. 2. For distributions: Use package manager (apt/yum/dnf) to update kernel package. 3. Reboot into new kernel if not using kexec or livepatch.
🔧 Temporary Workarounds
Avoid concurrent Btrfs operations
allAvoid running scrub and relocation operations simultaneously on Btrfs filesystems
# Monitor Btrfs operations and ensure they don't overlap
# Use 'btrfs scrub status' and 'btrfs balance status' to check current operations
Disable Btrfs scrub during maintenance
allTemporarily disable scrub when performing block group relocation or balance operations
# Cancel any running scrub: btrfs scrub cancel /mountpoint
# Perform relocation/balance operations
# Resume scrub when complete: btrfs scrub start /mountpoint
🧯 If You Can't Patch
- Avoid using Btrfs scrub and relocation features simultaneously
- Implement monitoring for Btrfs operation deadlocks and have manual recovery procedures ready
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if Btrfs is in use: uname -r and check /proc/filesystems for btrfsCheck Version:
uname -rVerify Fix Applied:
Verify kernel version contains fix commits or is newer than affected versions📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing 'BTRFS: Transaction aborted' with deadlock warnings
- System logs showing hung tasks related to btrfs processes
- Messages about 'blocked for more than 120 seconds' for btrfs tasks
Network Indicators:
- None - this is a local filesystem issue
SIEM Query:
source="kernel" AND "BTRFS: Transaction aborted" OR "btrfs.*blocked for more than"