CVE-2026-42013

A flaw was found in gnutls. When validating certificates, an oversized Subject Alternative Name (SAN) could cause the validation process to incorrectly fall back to checking the Common Name (CN) field. This could allow a remote attacker to bypass proper certificate validation, potentially leading to spoofing or man-in-the-middle attacks.

Database specific

{
    "cna_assigner": "redhat",
    "cwe_ids": [
        "CWE-295"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42013.json"
}

References

Affected packages

Git / gitlab.com/gnutls/gnutls

Affected ranges

Type

GIT

Repo

https://gitlab.com/gnutls/gnutls

Events

Introduced

Last Affected

Database specific

Show details

{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "last_affected": "0"
        }
    ],
    "source": "AFFECTED_FIELD"
}

Affected versions

Other

Database specific

source

"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-42013.json"