CVE-2026-74348: Linux kernel · ocfs2/dlm: require a ref for locking_state debugfs open
Affects Linux kernelSource GCVE Database
Not known to be exploited · fixed in 5.15.0-1117.124~20.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 12:55 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 12% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +41
Exploitation evidence
Disclosed: evidence found.
CVE published 15 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available that fixes this vulnerability by making debug_lockres_open() fail if dlm_grab() cannot acquire a reference, preventing the use-after-free. Users should apply the official Linux kernel updates that include this fix. No additional mitigation is required beyond applying the patch.
Description
A use-after-free vulnerability in the Linux kernel's ocfs2/dlm locking_state debugfs interface was resolved. The flaw occurs because debug_lockres_open() ignores the return value of dlm_grab(), potentially storing a NULL pointer after the last domain unregister removes the context. This leads to a use-after-free when debug_lockres_release() later calls dlm_put() on a freed context. The issue was detected by KASAN and affects specific Linux kernel versions. A patch is available that causes open to fail if dlm_grab() cannot acquire the reference, preventing the use-after-free condition.
References
- nvd.nist.gov/vuln/detail/CVE-2026-74348 (opens in a new tab)
- git.kernel.org/stable/c/03ad858ce8064861ea580021976dc19b7aabb549 (opens in a new tab)
- git.kernel.org/stable/c/5bee5d5f67aedd26d2b72e00e49dd93331fbcc30 (opens in a new tab)
- git.kernel.org/stable/c/6cc93dea4078cbcddee63fa2234e382a76600464 (opens in a new tab)
- git.kernel.org/stable/c/90a6512425414098a63fc97b77bed089c75d106b (opens in a new tab)
- git.kernel.org/stable/c/9c81c1a61a52b6ecf0d14f1dbd95f154a7a9e92a (opens in a new tab)
- git.kernel.org/stable/c/a087b2d3411e7f9df71ba3293596923ee2c70d65 (opens in a new tab)
- git.kernel.org/stable/c/a09831214912a1f270663d935613910fafd8d883 (opens in a new tab)
- git.kernel.org/stable/c/aa7883b6a3c76301a3299deb34de948e73bb6a08 (opens in a new tab)
- ubuntu.com/security/CVE-2026-74348 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-74348 (opens in a new tab)
- git.kernel.org/linus/03ad858ce8064861ea580021976dc19b7aabb549 (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8889-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8887-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8888-2 (opens in a new tab)