CVE-2026-5778

medium

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

CVSS v3

6.5

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

CVSS v2

—

VIR risk

6.5

Description

Integer underflow in wolfSSL packet sniffer <= 5.9.0 allows an attacker to cause a program crash in the AEAD decryption path by injecting a TLS record shorter than the explicit IV plus authentication tag into traffic inspected by ssl_DecodePacket. The underflow wraps a 16-bit length to a large value that is passed to AEAD decryption routines, causing a large out-of-bounds read and crash. An unauthenticated attacker can trigger this remotely via malformed TLS Application Data records.

Predictions

Exploit likelihood

75%

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-2026-5778

vendor Authored 2026-05-27

Vendor advisory: facts@wolfssl.com — https://github.com/wolfSSL/wolfssl/pull/10125

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

CWEs

CWE-191

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