| Name | CVE-2026-5188 |
| Description | An integer underflow issue exists in wolfSSL when parsing the Subject Alternative Name (SAN) extension of X.509 certificates. A malformed certificate can specify an entry length larger than the enclosing sequence, causing the internal length counter to wrap during parsing. This results in incorrect handling of certificate data. The issue is limited to configurations using the original ASN.1 parsing implementation which is off by default. |
| 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/10024
Fixed by (merge): https://github.com/wolfSSL/wolfssl/commit/0f41e99c34c956ddea66e732b7db7828b7e2a403 (v5.9.1-stable)