Vulnerability in Linux
CVE-2026-53394
In the Linux kernel, the following vulnerability has been resolved: nfsd: avoid leaking pre-allocated openowner on unconfirmed retry race When find_or_alloc_open_stateowner() encounters an unconfirmed owner, it calls release_openowner() and sets oo = NULL. Control then falls through past the `if (oo)` guard -- which would have freed any pre-allocated `new` -- and unconditionally executes `new = alloc_stateowner(...)`. If `new` was already allocated on a prior iteration, the pointer is silently overwritten and the previous allocation (slab object + owner name buffer) is leaked. This requires a race: two NFSv4.0 OPEN threads with the same owner string, where a concurrent thread inserts a new unconfirmed owner into the hash between retry iterations. The window is narrow but repeatable under adversarial conditions. Fix by adding `goto retry` after `oo = NULL` so the already-allocated `new` is reused on the next iteration rather than overwritten.
EPSS: 0.005 (39.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Linux — versions 6.18.38, 7.2-rc1, 7.2
- Linux Linux_kernel
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-53394?
- CVE-2026-53394 is a high-severity vulnerability in Linux, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 7.5/10. Published 2026-07-19.
- How severe is CVE-2026-53394?
- High severity. CVSS v3 base score is 7.5 out of 10.