CVE-2026-5187

Name	CVE-2026-5187
Description	Two potential heap out-of-bounds write locations existed in DecodeObjectId() in wolfcrypt/src/asn.c. First, a bounds check only validates one available slot before writing two OID arc values (out[0] and out[1]), enabling a 2-byte out-of-bounds write when outSz equals 1. Second, multiple callers pass sizeof(decOid) (64 bytes on 64-bit platforms) instead of the element count MAX_OID_SZ (32), causing the function to accept crafted OIDs with 33 or more arcs that write past the end of the allocated buffer.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs	1133835

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
wolfssl (PTS)	bullseye	4.6.0+p1-0+deb11u2	vulnerable
	bookworm	5.5.4-2+deb12u2	vulnerable
	trixie	5.7.2-0.1+deb13u1	vulnerable
	sid, forky	5.9.1-0.1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
wolfssl	source	(unstable)	5.9.1-0.1			1133835

Notes

[trixie] - wolfssl <no-dsa> (Minor issue)
[bookworm] - wolfssl <no-dsa> (Minor issue)
[bullseye] - wolfssl <postponed> (Minor issue)
https://github.com/wolfSSL/wolfssl/pull/10025
Fixed by (merge): https://github.com/wolfSSL/wolfssl/commit/3cf4aeab5c617821ea197566082cc047320ff174 (v5.9.1-stable)