CVE-2023-53668
📋 TL;DR
This CVE describes a denial-of-service vulnerability in the Linux kernel's ring buffer tracing subsystem. When reading from trace_pipe, a race condition during ring buffer resizing can cause an infinite loop, leading to a kernel soft lockup. This affects any Linux system with kernel tracing enabled.
💻 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 →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 unresponsiveness requiring hard reboot, potentially causing data loss or service disruption.
Likely Case
System becomes unresponsive when trace_pipe is accessed, requiring reboot of affected system.
If Mitigated
Minimal impact if kernel tracing is disabled or access to trace_pipe is restricted.
🎯 Exploit Status
Requires ability to read from /sys/kernel/debug/tracing/trace_pipe or similar tracing interfaces. Typically requires local access or ability to execute code on the system.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Multiple stable kernel versions with fixes: 0a29dae5786d, 27bdd93e44cc, 5e68f1f3a20f, 7e42907f3a7b, 8b0b63fdac6b
Vendor Advisory: https://git.kernel.org/stable/c/0a29dae5786d263016a9aceb1e56bf3fd4cc6fa0
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution vendor. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable kernel tracing
linuxPrevent access to trace_pipe by disabling kernel tracing functionality
echo 0 > /sys/kernel/debug/tracing/tracing_on
chmod 000 /sys/kernel/debug/tracing/trace_pipe
Restrict trace_pipe access
linuxLimit which users can access the trace_pipe file
chmod 600 /sys/kernel/debug/tracing/trace_pipe
setfacl -m u:root:rw- /sys/kernel/debug/tracing/trace_pipe
🧯 If You Can't Patch
- Disable kernel tracing subsystem entirely
- Implement strict access controls on /sys/kernel/debug/tracing/ directory
🔍 How to Verify
Check if Vulnerable:
Check if kernel version is unpatched and tracing is enabled: cat /sys/kernel/debug/tracing/tracing_onCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes one of the fix commits and test trace_pipe reading functionality📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing 'soft lockup' messages
- Watchdog timeout errors in system logs
- High CPU usage from kernel processes
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("soft lockup" OR "watchdog: BUG") AND "trace_pipe"🔗 References
- https://git.kernel.org/stable/c/0a29dae5786d263016a9aceb1e56bf3fd4cc6fa0
- https://git.kernel.org/stable/c/27bdd93e44cc28dd9b94893fae146b83d4f5b31e
- https://git.kernel.org/stable/c/5e68f1f3a20fe9b6bde018e353269fbfa289609c
- https://git.kernel.org/stable/c/7e42907f3a7b4ce3a2d1757f6d78336984daf8f5
- https://git.kernel.org/stable/c/8b0b63fdac6b70a45614e7d4b30e5bbb93deb007
- https://git.kernel.org/stable/c/a55e8a3596048c2f7b574049aeb1885b5abba1cc
- https://git.kernel.org/stable/c/bb14a93bccc92766b1d9302c6bcbea17d4bce306
- https://git.kernel.org/stable/c/e84829522fc72bb43556b31575731de0440ac0dd
