A heap buffer overflow is triggered in the CertFromX509 function when processing the AuthorityKeyIdentifier extension of an X.509 certificate. The implementation incorrectly calculates the buffer size required for the extension, causing an out‑of‑bounds write on the heap. This memory corruption can enable an attacker to overwrite adjacent data, potentially leading to arbitrary code execution or application crashes, depending on the context in which the certificate is parsed.

The flaw appears in the wolfSSL library supplied by wolfSSL. No specific release versions are mentioned in the description, so any build containing the current CertFromX509 implementation could be vulnerable unless corrected by the vendor. Version information is not provided.

The CVSS score of 6.3 indicates moderate severity. EPSS data is unavailable, and the issue is not listed in the CISA KEV catalog. Exploitation requires an attacker to supply a crafted certificate to an application that uses wolfSSL for certificate parsing. Because the overflow occurs on the heap, an attacker may achieve remote code execution or cause a denial of service if the vulnerable component is exposed to untrusted input. The attack vector is inferred to be remote through untrusted certificates, such as those received over a network or from a user‑supplied source.