CVE-2026-5188 — Integer underflow in X.509 SAN parsing in wolfSSL
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…
Published: 2026-04-10 · CVSS: 2.3 · CVSS 4.0
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 Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7