CVE-2026-23149
📋 TL;DR
This CVE addresses a kernel warning trigger vulnerability in the Linux kernel's DRM subsystem. Attackers with local access can trigger kernel warnings by passing specially crafted handle values to the drm_gem_change_handle_ioctl() function. This affects Linux systems with DRM graphics support enabled.
💻 Affected Systems
- Linux kernel
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Repeated triggering could cause kernel log spam, potential denial of service through log flooding, or system instability if warnings are treated as errors.
Likely Case
Local users can trigger kernel warnings in system logs, creating noise and potentially masking other security events.
If Mitigated
With proper access controls limiting local user privileges, impact is minimal as only warning messages are generated.
🎯 Exploit Status
Exploitation requires local access and knowledge of the vulnerable ioctl interface. The vulnerability only triggers warnings, not crashes or privilege escalation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits 12f15d52d38ac53f7c70ea3d4b3d76afed04e064 and ae8831ee0fb2f5f41f39722e7b3749d65bb78d08
Vendor Advisory: https://git.kernel.org/stable/c/12f15d52d38ac53f7c70ea3d4b3d76afed04e064
Restart Required: No
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. For distributions: Use package manager to update kernel package. 3. Rebuild kernel if using custom kernel with the fix commits backported.
🔧 Temporary Workarounds
Restrict DRM device access
allLimit access to DRM devices to prevent unauthorized users from calling the vulnerable ioctl
chmod 600 /dev/dri/card*
chown root:video /dev/dri/card*
🧯 If You Can't Patch
- Implement strict access controls on /dev/dri devices to limit which users can access DRM functionality
- Monitor kernel logs for warning messages from drm_gem_change_handle_ioctl to detect exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check kernel version and whether it contains the vulnerable code. Examine /proc/version or uname -r and compare with distribution security advisories.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes the fix commits or check with distribution-specific security update verification tools.📡 Detection & Monitoring
Log Indicators:
- Kernel warning messages containing 'drm_gem_change_handle_ioctl' or 'idr_alloc' with start < 0 warnings
Network Indicators:
- None - local-only vulnerability
SIEM Query:
source="kernel" AND ("drm_gem_change_handle_ioctl" OR "idr_alloc" AND "start < 0")