CVE-2026-53394CWE-401

CVE-2026-53394

High · published July 19, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
39.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00465 · 39.3th percentile
Weakness
CWE-401 · Missing Release of Memory after Effective Lifetime
Published
2026-07-19T16:16Z
Affected products (3)
ProductVersionsFixed in
linux/linux_kernel≥ 6.10, < 6.12.956.12.95
linux/linux_kernel≥ 6.13, < 6.18.386.18.38
linux/linux_kernel≥ 6.19, < 7.1.37.1.3
References (4)
EPSS history
Timeline
  • 19 JUL 12:01Z
    nfsd: avoid leaking pre-allocated openowner on unconfirmed retry race
    cvelistv5