CVE-2026-53341: Linux kernel · fhandle: fix UAF due to unlocked ->mnt_ns read in may_decode_fh()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 7.0.0-31.31~24.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 7.0.0-31.31~24.04.1, 7.0.0-1018.18~24.04.1, 7.0.0-31.31 +14
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 1 Jul 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 fix is available and has been released in Linux kernel versions 7.0.0-31.31 and later. Users should update to these fixed kernel versions to remediate the vulnerability. No additional mitigation is required as the issue is addressed by the official patch.
Description
A use-after-free (UAF) vulnerability in the Linux kernel's fhandle subsystem was fixed. The flaw involved accessing the mount namespace without proper locking, which could lead to a race condition and potential kernel crash or information leakage. This issue requires specific kernel configurations (CONFIG_PREEMPTION or CONFIG_RCU_STRICT_GRACE_PERIOD) to be exploitable. The vulnerability has been addressed in Linux kernel versions 7.0.0-31.31 and later.
References
- ubuntu.com/security/CVE-2026-53341 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-53341 (opens in a new tab)
- git.kernel.org/linus/40ab6644b99685755f740b872c00ef40d9aa870e (opens in a new tab)
- git.kernel.org/stable/c/32138633e51e6db59e474765cf93268c92b42888 (opens in a new tab)
- git.kernel.org/stable/c/40ab6644b99685755f740b872c00ef40d9aa870e (opens in a new tab)
- git.kernel.org/stable/c/a8ed2c29fcfdac78db96c9da4e659c8a513f2a94 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8800-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-3 (opens in a new tab)