CVE-2026-42791
- Source
- https://cve.org/CVERecord?id=CVE-2026-42791
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-42791.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-42791
- Aliases
-
- EEF-CVE-2026-42791
- GHSA-cjxj-wj6x-3fff
- Downstream
- Related
- Published
- 2026-05-27T12:23:13Z
- Modified
- 2026-08-21T09:27:06Z
- Severity
-
- 6.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N CVSS Calculator
- Summary
- OCSP responder certificate validity period not checked in public_key
- Details
-
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.
OCSP 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.
This 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. It also affects applications calling public_key:pkix_ocsp_validate/5 directly, where the impact depends on the use case — server-side client certificate validation using this API may allow authentication bypass with a revoked client certificate.
This issue affects OTP from OTP 27.0 before OTP 29.0.1, OTP 28.5.0.1 and OTP 27.3.4.12, corresponding to public_key from 1.16 before 1.21.1, 1.20.3.1 and 1.17.1.3.
- Database specific
{ "cna_assigner": "EEF", "cwe_ids": [ "CWE-295", "CWE-672" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42791.json", "unresolved_ranges": [ { "extracted_events": [ { "introduced": "1.16" }, { "fixed": "*" }, { "introduced": "27.0" }, { "fixed": "*" }, { "introduced": "2b1a742c651b90f8a7a1fb2ddde73f29915ea376" }, { "fixed": "*" } ], "source": "AFFECTED_FIELD" } ] }- References
-
- https://cna.erlef.org/cves/CVE-2026-42791.html
- https://github.com
- https://osv.dev/vulnerability/EEF-CVE-2026-42791
- https://www.erlang.org/doc/system/versions.html#order-of-versions
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42791.json
- https://github.com/erlang/otp/security/advisories/GHSA-cjxj-wj6x-3fff
- https://nvd.nist.gov/vuln/detail/CVE-2026-42791
- https://github.com/erlang/otp/commit/7995f1fdaee3da569bb810358ce0f546471d169b
- https://github.com/erlang/otp/commit/b3870e02405c709a872b01ba6086065620cdfe76
- https://github.com/erlang/otp
Affected packages
Git / github.com/erlang/otp
Affected ranges
- Type
- GIT
- Repo
- https://github.com/erlang/otp
- Events
-
IntroducedFixedIntroducedFixedIntroducedFixedFixedFixed
- Database specific
-
Show details
{ "cpe": "cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*", "extracted_events": [ { "introduced": "27.0" }, { "fixed": "27.3.4.12" }, { "introduced": "28.0" }, { "fixed": "28.5.0.1" }, { "introduced": "29.0" }, { "fixed": "29.0.1" } ], "source": [ "CPE_RANGE", "REFERENCES" ] }