PT-2026-61099 · Linux · Linux

CVE-2026-53394 · Published 2026-07-19 · Updated 2026-07-19

NVD

CVSS v3.1

7.5

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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.

Fix

Related Identifiers

CVE-2026-53394

Affected Products

Linux

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2026-53394 · Security Note
• https://git.kernel.org/stable/c/57aee7a35bb12753057c5b65d72d1f46c0e95b07 · Note
• https://git.kernel.org/stable/c/017a6150106b054cc84d1b0582d97bd3a74d4281 · Note
• https://git.kernel.org/stable/c/c9aefb2b5f11337c9202c5bd0c45d71198449718 · Note
• https://git.kernel.org/stable/c/a10bf67fe06469a71a401f72f328237345d553c0 · Note