{"api_version":"1","generated_at":"2026-06-02T09:43:02+00:00","cve":"CVE-2026-42791","urls":{"html":"https://cve.report/CVE-2026-42791","api":"https://cve.report/api/cve/CVE-2026-42791.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-42791","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-42791"},"summary":{"title":"OCSP responder certificate validity period not checked in public_key","description":"Improper Certificate Validation vulnerability in Erlang OTP public_key (pubkey_ocsp module) allows forged OCSP responses signed with an expired responder certificate to be accepted as valid.\n\nOCSP response verification in pubkey_ocsp:verify_response/5 and pubkey_ocsp:is_authorized_responder/3 in lib/public_key/src/pubkey_ocsp.erl does not check the validity period (notBefore/notAfter) of the OCSP responder certificate. An attacker who has obtained the private key of an expired CA-designated OCSP responder certificate can forge OCSP responses that Erlang/OTP accepts as valid.\n\nThis affects TLS clients using OCSP stapling via the ssl application: a malicious or compromised server can present a revoked TLS certificate together with a forged OCSP response signed by an expired responder key, and the client will accept the revoked certificate as valid. 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