CVE-2022-50539
📋 TL;DR
This CVE describes a refcount leak bug in the Linux kernel's ARM OMAP2+ omap4-common module. The vulnerability occurs when the kernel fails to properly release a reference count after using a device tree node, potentially leading to memory exhaustion or system instability. This affects Linux systems running on ARM OMAP2+ hardware with vulnerable kernel versions.
💻 Affected Systems
- Linux Kernel
⚠️ Risk & Real-World Impact
Worst Case
Sustained exploitation could lead to kernel memory exhaustion, causing system crashes, denial of service, or potential privilege escalation if combined with other vulnerabilities.
Likely Case
Local attackers could trigger the refcount leak repeatedly to cause memory exhaustion, leading to system instability or denial of service on affected ARM devices.
If Mitigated
With proper access controls and kernel hardening, impact is limited to denial of service from local users, with no remote exploitation vector.
🎯 Exploit Status
Exploitation requires local access and knowledge of triggering the specific code path. No public exploits are known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits 049875b76660bbdc4873a915afb294f954eb7320, 1d9452ae3bdb830f9309cf10a2f65977999cb14e, or 7c32919a378782c95c72bc028b5c30dfe8c11f82
Vendor Advisory: https://git.kernel.org/stable/c/049875b76660bbdc4873a915afb294f954eb7320
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 OMAP4 SRAM initialization if not needed
linuxIf system doesn't require OMAP4 SRAM functionality, prevent the vulnerable code path from executing
echo 'blacklist omap4_common' >> /etc/modprobe.d/blacklist.conf
🧯 If You Can't Patch
- Restrict local user access to prevent potential exploitation
- Implement kernel memory monitoring to detect abnormal memory consumption patterns
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if running on ARM OMAP2+ hardware: uname -r && cat /proc/cpuinfo | grep -i omapCheck Version:
uname -rVerify Fix Applied:
Verify kernel version contains one of the fix commits: grep -r '049875b76660bbdc4873a915afb294f954eb7320\|1d9452ae3bdb830f9309cf10a2f65977999cb14e\|7c32919a378782c95c72bc028b5c30dfe8c11f82' /usr/src/linux-headers-$(uname -r)/📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages
- Out of memory errors in dmesg
- System instability logs
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("oom" OR "panic" OR "BUG") AND process="omap4"