{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-42791 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-42791 is a medium-severity vulnerability in Erlang OTP, published on 27 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-42791 and fix it if it is affected.\n\nWhat it is: CVE-2026-42791 is a medium-severity vulnerability in Erlang OTP, published on 27 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-42791 in the wild and no public exploit code.\n\nAffected product: Erlang OTP. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-42791/ (Markdown: https://insights.sbomify.com/CVE-2026-42791/index.md)","id":"CVE-2026-42791","markdown":"https://insights.sbomify.com/CVE-2026-42791/index.md","name":"CVE-2026-42791","record":{"aliases":["DEBIAN-CVE-2026-42791","EEF-CVE-2026-42791","GHSA-cjxj-wj6x-3fff","UBUNTU-CVE-2026-42791"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":false,"product_category":"Erlang OTP public_key","requires_auth":"none","summary":"Attackers can bypass TLS certificate revocation checks by forging OCSP responses with expired responder keys, allowing revoked certificates to be accepted as valid.","user_interaction":"not_required","vuln_class":"security_feature_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[{"product":"erlang\\/otp","vendor":"erlang"}],"cvss":{"score":6.3,"severity":"medium","source":"cna","vector":"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","version":"4.0"},"cwes":[{"id":"CWE-672","name":"Operation on a Resource after Expiration or Release"},{"id":"CWE-295","name":"Improper Certificate Validation"}],"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. 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.\n\nThis 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.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"OCSP responder certificate validity period not checked in public_key","id":"CVE-2026-42791","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"security_feature_bypass","year":"2026"},"n_packages":0,"n_references":6,"next":{"headline":"epmd permanent DoS via EMFILE on accept(2) in erts","id":"CVE-2026-42792"},"packages":[],"prev":{"headline":"nameConstraints DNS bypass via subject CommonName fallback in public_key hostname verification","id":"CVE-2026-42790"},"products":["OTP"],"published":"2026-05-27","related":[{"cvss_score":9.8,"headline":"Auth bypass in n/a","id":"CVE-2022-37026","kev_date_added":null,"published":"2022-09-21"},{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2016-10253","kev_date_added":null,"published":"2017-03-18"},{"cvss_score":9.1,"headline":"TLS 1.2 and DTLS client accepts unoffered anonymous cipher suite, bypassing server authentication","id":"CVE-2026-55953","kev_date_added":null,"published":"2026-07-27"},{"cvss_score":8.8,"headline":"Stack buffer overflow in SCTP error cause parsing in inet_drv allows remote VM crash","id":"CVE-2026-49759","kev_date_added":null,"published":"2026-06-10"},{"cvss_score":8.7,"headline":"TLS/DTLS denial of service via unbounded recursion on cross-signed peer certificate chain","id":"CVE-2026-58227","kev_date_added":null,"published":"2026-07-27"},{"cvss_score":8.7,"headline":"Denial of service via exponential certificate policy tree growth in path validation","id":"CVE-2026-59251","kev_date_added":null,"published":"2026-07-27"},{"cvss_score":8.7,"headline":"DTLS listener crash via race condition in dtls_packet_demux causes denial of service for all sessions","id":"CVE-2026-55950","kev_date_added":null,"published":"2026-07-02"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-07-24","vendors":["Erlang"]},"summary":"Attackers can bypass TLS certificate revocation checks by forging OCSP responses with expired responder keys, allowing revoked certificates to be accepted as valid.","url":"https://insights.sbomify.com/CVE-2026-42791/"}