CVE-2026-40399

high

Published 2026-05-12 · Modified 2026-06-01

💬 Discuss on Community ✚ Propose mitigation

CVSS v3

7.8

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

CVSS v4 NEW

—

not yet in upstream

VIR risk

7.8

Description

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows TCP/IP allows an authorized attacker to elevate privileges locally.

Predictions

Exploit likelihood

75%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

Windows Affected 1 release

Version	Status	Fixed in
—	Affected	`10.0.14393.9140`

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40399

CWEs

CWE-121

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.