Integer underflow in X.509 SAN parsing in wolfSSL_CVE-2026-5188

2.3 / 10

LOW

CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N

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.

Basic Information

ID CVE-2026-5188

Source wolfSSL

Published Apr 10, 2026 at 03:24

Modified Apr 10, 2026 at 13:41

Affected Product

Vendor wolfSSL

Product wolfSSL

Affected Versions wolfSSL wolfSSL 0

CWE Classification

CWE-191

References

github.com /wolfSSL/wolfssl/pull/10024

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    "published": "2026-04-10T03:24:21.126Z",
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