CVE-2022-28796
📋 TL;DR
CVE-2022-28796 is a use-after-free vulnerability in the Linux kernel's jbd2 journaling subsystem caused by a transaction_t race condition. This allows local attackers to potentially escalate privileges or cause denial of service. Systems running Linux kernel versions before 5.17.1 are affected.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Fedora by Fedoraproject
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 →Solidfire \& Hci Management Node by Netapp
⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation to root, kernel panic leading to system crash, or arbitrary code execution in kernel context.
Likely Case
Kernel panic causing system instability or denial of service, potentially leading to data corruption in journaled filesystems.
If Mitigated
Limited impact if proper access controls restrict local user accounts and system runs with minimal privileges.
🎯 Exploit Status
Exploitation requires local access and precise timing to trigger the race condition. No public exploits have been documented.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel 5.17.1 and later
Vendor Advisory: https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.1
Restart Required: Yes
Instructions:
1. Update Linux kernel to version 5.17.1 or later. 2. For distributions: Use package manager (apt-get upgrade linux-image, yum update kernel, etc.). 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable jbd2 journaling
linuxTemporarily disable journaling on ext4 filesystems (not recommended for production due to data integrity risks)
tune2fs -O ^has_journal /dev/sdX
e2fsck -f /dev/sdX
Restrict local user access
allLimit shell access and local login capabilities to trusted users only
🧯 If You Can't Patch
- Implement strict access controls to limit local user accounts and shell access
- Monitor system logs for kernel panic events and unauthorized privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check kernel version with 'uname -r'. If version is earlier than 5.17.1, system is vulnerable.Check Version:
uname -rVerify Fix Applied:
After patching, verify kernel version is 5.17.1 or later with 'uname -r' and check system stability.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log or dmesg
- Unexpected privilege escalation events in audit logs
- System crash/reboot events
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="kern.log" AND "kernel panic" OR source="audit.log" AND "privilege escalation"🔗 References
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.1
- https://github.com/torvalds/linux/commit/cc16eecae687912238ee6efbff71ad31e2bc414e
- https://security.netapp.com/advisory/ntap-20220506-0006/
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.17.1
- https://github.com/torvalds/linux/commit/cc16eecae687912238ee6efbff71ad31e2bc414e
- https://security.netapp.com/advisory/ntap-20220506-0006/
