An integer underflow occurs in the X.509 Subject Alternative Name parsing routine of wolfSSL. A malformed certificate can declare a length larger than the surrounding ASN.1 sequence, causing an internal length counter to wrap and the library to misinterpret the data. The defect limits the handling of certificate content, potentially leading to invalid certificate validation or denial of service. No known exploitation beyond incorrect parsing has been reported.

The flaw affects the wolfSSL library. It is present only in configurations that use the original ASN.1 parsing implementation, which is disabled by default. No specific version information is supplied, so any deployment employing the legacy parser may be susceptible.

The CVSS score of 2.3 indicates low severity, and the EPSS score is not available. The vulnerability is not listed in the CISA KEV catalog. Attackers could potentially supply crafted certificates over the network to trigger the underflow, but exploitation is constrained by the need to use the legacy parser. The likelihood of exploitation is uncertain and likely low without a broader vulnerability impact.