CVE-2026-5264

critical

Published 2026-04-09 · Modified 2026-04-29

CVSS v3

9.8

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

CVSS v2

—

VIR risk

9.8

Description

Heap buffer overflow in DTLS 1.3 ACK message processing. A remote attacker can send a crafted DTLS 1.3 ACK message that triggers a heap buffer overflow.

Predictions

Exploit likelihood

97%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2026-5264

vendor Authored 2026-05-27

Vendor advisory: facts@wolfssl.com — https://github.com/wolfssl/wolfssl/pull/10076

OS impact

OS	Version	Status	Fixed in
debian	bookworm	affected
debian	bullseye	affected
debian	forky	fixed	`5.9.1-0.1`
debian	sid	fixed	`5.9.1-0.1`
debian	trixie	affected

Application impact

Vendor	Product	Versions	Fixed
wolfssl	wolfssl	`{"endExcluding":"5.9.1"}`	`5.9.1`

References

https://github.com/wolfssl/wolfssl/pull/10076
https://security-tracker.debian.org/tracker/CVE-2026-5264

CWEs

CWE-122

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