CVE-2022-49259
📋 TL;DR
This CVE describes a kernel-level race condition in the Linux block subsystem where a parent kobject is deleted before its child kobjects, potentially causing system instability. The vulnerability can trigger kernel warnings and system crashes, affecting all Linux systems using the vulnerable kernel versions. While not directly exploitable for privilege escalation, it can lead to denial of service.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic or system crash leading to complete denial of service, potentially requiring physical access to reboot affected systems.
Likely Case
Kernel warning messages in system logs and potential system instability during storage operations, but no direct privilege escalation.
If Mitigated
Minor performance impact during storage operations with warning messages in logs, but system remains operational.
🎯 Exploit Status
Exploitation requires local access and specific conditions to trigger the race condition. No known weaponized exploits exist.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Multiple stable kernel versions with fixes (see git references in CVE)
Vendor Advisory: https://git.kernel.org/stable/c/0b5924a14d64487ebd51127b0358d06066ef5384
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 block crypto subsystem
linuxPrevent triggering of vulnerable code path by disabling cryptographic block device support
echo 'blacklist blk-crypto' > /etc/modprobe.d/disable-blk-crypto.conf
update-initramfs -u
reboot
🧯 If You Can't Patch
- Monitor system logs for 'sysfs group not found' warnings and restart affected services
- Avoid operations that trigger block device removal while crypto operations are active
🔍 How to Verify
Check if Vulnerable:
Check kernel version against known vulnerable ranges and examine dmesg for 'sysfs group not found for kobject crypto' warningsCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is updated to patched version and no related warnings appear in system logs after patch application📡 Detection & Monitoring
Log Indicators:
- WARNING: CPU: 0 PID: 1 at fs/sysfs/group.c:278 sysfs_remove_group
- sysfs group 'modes' not found for kobject 'crypto'
- Call Trace including blk_crypto_sysfs_unregister
Network Indicators:
- None - this is a local kernel issue
SIEM Query:
source="kernel" AND ("sysfs_remove_group" OR "blk_crypto_sysfs_unregister" OR "sysfs group not found for kobject crypto")🔗 References
- https://git.kernel.org/stable/c/0b5924a14d64487ebd51127b0358d06066ef5384
- https://git.kernel.org/stable/c/0f69288253e9fc7c495047720e523b9f1aba5712
- https://git.kernel.org/stable/c/3d7e32c8da45957326f56937e0471c686d1a7711
- https://git.kernel.org/stable/c/84fe3ca6e7910beb47ec13509d484f84fa2a41ad
- https://git.kernel.org/stable/c/b2001eb10f59363da930cdd6e086a2861986fa18
- https://git.kernel.org/stable/c/cf0cb8686e55d9c022944bc6ba9e19e832889e83
- https://git.kernel.org/stable/c/efaa0e969261e97c1fdd8e0338e5dd3ba5b9219c
