CVE-2026-53381
HIGH 7.8In the Linux kernel, the following vulnerability has been resolved: virtiofs: fix UAF on submount umount iput() called from fuse_release_end() can Oops if the super block has already been destroyed. Normally this is prevented by waiting for num_waiting to go down to zero before commencing with super block shutdown. This only works, however, for the last submount instance, as the wait counter is per connection, not per superblock. Revert to using synchronous release requests for the auto_submounts case, which is virtiofs only at this time.
Severe if exploited (CVSS 7.8), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.1%chance of exploitation in 30 days · 3rd percentile
Impact if exploited
7.8CVSS 3.1 · HIGH
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ⚠Access: Requires local access to the host
- ⚠Privileges: Requires a low-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-53381/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-53381/poc.json
Weakness (CWE)
Not classified.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
All CVSS metrics
- HIGH 7.8 v3.1 · CNA Primary
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - HIGH 7.8 v3.1 · NVD Secondary
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
References
Technical & other
- https://git.kernel.org/stable/c/607a1d4c42f649e6197567c0448fd9ebb316cd42
- https://git.kernel.org/stable/c/1cc0e3a0c6499aaaa2f21a4fcbba388486afb25e
- https://git.kernel.org/stable/c/0b809199ff87c44487e516a725dd4be2185712ce
- https://git.kernel.org/stable/c/2181a09ba980f142650fb053666350ead4471cfe
- https://git.kernel.org/stable/c/97c4691653d145dcc699eca5d3aba3219a520f1f
- https://git.kernel.org/stable/c/2abfd3ffbd9452f72535d96ff3982b3ab1f8f2f9
- https://git.kernel.org/stable/c/39a2b95e008665c14f84e50ed411d898df7cd11b
- https://git.kernel.org/stable/c/e09412a714bcd49375198427bb4aa005037a9d6f
- https://git.kernel.org/stable/c/06b41351779e9289e8785694ade9042ae85e41ea