CVE-2025-38267
📋 TL;DR
This CVE describes a Linux kernel vulnerability in the ring buffer subsystem where a commit_overrun scenario can trigger a WARN_ON_ONCE() warning. This is a denial-of-service vulnerability that can cause kernel warnings and potential system instability when specific tracing conditions occur. All Linux systems using affected kernel versions are potentially vulnerable.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
System crash or kernel panic due to triggered warnings under heavy tracing load, leading to denial of service.
Likely Case
Kernel warning messages in logs and potential performance degradation during intensive tracing operations.
If Mitigated
Minor performance impact during tracing operations with no system instability.
🎯 Exploit Status
Exploitation requires specific tracing configurations and kernel debugging features enabled. The vulnerability was discovered during testing with perf and trace-cmd under heavy load.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees (commits: 4fc78a7c9ca994e1da5d3940704d4e8f0ea8c5e4, b8df8cb8f7eef52baa9ac5bf36a405ca67945a91, e018053632bad8ee0752242c7d2cffb0bbf45404)
Vendor Advisory: https://git.kernel.org/stable/c/4fc78a7c9ca994e1da5d3940704d4e8f0ea8c5e4
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution's repositories. 2. Reboot system to load new kernel. 3. Verify kernel version matches patched release.
🔧 Temporary Workarounds
Disable kernel tracing features
linuxDisable perf, ftrace, and other kernel tracing subsystems to prevent the commit_overrun condition
echo 0 > /sys/kernel/debug/tracing/tracing_on
echo 0 > /proc/sys/kernel/perf_event_paranoid
Disable kernel debugging features
linuxDisable lockdep, KASAN, and kmemleak debugging features that were part of the triggering scenario
Remove kernel boot parameters: lockdep, kasan, kmemleak from GRUB configuration
🧯 If You Can't Patch
- Restrict access to tracing tools (perf, trace-cmd) to trusted administrators only
- Monitor system logs for WARNING messages related to ring_buffer_map_get_reader
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if running with lockdep, KASAN, kmemleak enabled while using perf/trace-cmdCheck Version:
uname -rVerify Fix Applied:
Check kernel version matches patched release and verify no WARNING messages appear in dmesg during tracing operations📡 Detection & Monitoring
Log Indicators:
- Kernel WARNING messages containing 'ring_buffer_map_get_reader'
- dmesg warnings about commit_overrun or missed_events
Network Indicators:
- None - this is a local kernel vulnerability
SIEM Query:
source="kernel" AND "WARNING" AND "ring_buffer_map_get_reader"