{"id":"CVE-2026-42013","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-42013","generatedAt":"2026-10-28T02:19:07.847Z","title":"This could allow a remote attacker to bypass proper certificate validation, potentially leading to spoofing or man-in-the-middle attacks.","description":"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.","published":"2026-05-26T22:16:42.000Z","lastModified":"2026-10-14T20:17:43.000Z","status":"Awaiting Analysis","sourceIdentifier":"secalert@redhat.com","cvss":{"version":"3.1","score":8.2,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N"},"cwe":["CWE-295"],"affected":[],"epss":{"score":0.00423,"percentile":0.36313,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.42%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://access.redhat.com/errata/RHSA-2026:13274","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:20611","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:20612","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:20613","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:26319","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:26409","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:29197","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:30004","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:30849","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:30850","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:32962","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:33125","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:40762","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:41921","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:43575","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:56853","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:57483","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:58981","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:59831","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:60019","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:72502","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:74674","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:82304","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:82322","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:82347","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:82354","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:82372","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:82857","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:82888","source":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/cve/CVE-2026-42013","source":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2467448","source":"secalert@redhat.com"},{"url":"https://www.gnutls.org/security-new.html#GNUTLS-SA-2026-04-29-8","source":"secalert@redhat.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-42013","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}