{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-27459","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-02-19T17:25:31.100Z","datePublished":"2026-03-17T23:34:28.483Z","dateUpdated":"2026-03-18T19:52:15.812Z"},"containers":{"cna":{"title":"pyOpenSSL DTLS cookie callback buffer overflow","problemTypes":[{"descriptions":[{"cweId":"CWE-120","lang":"en","description":"CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"HIGH","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":7.2,"baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U","version":"4.0"}}],"references":[{"name":"https://github.com/pyca/pyopenssl/security/advisories/GHSA-5pwr-322w-8jr4","tags":["x_refsource_CONFIRM"],"url":"https://github.com/pyca/pyopenssl/security/advisories/GHSA-5pwr-322w-8jr4"},{"name":"https://github.com/pyca/pyopenssl/commit/57f09bb4bb051d3bc2a1abd36e9525313d5cd408","tags":["x_refsource_MISC"],"url":"https://github.com/pyca/pyopenssl/commit/57f09bb4bb051d3bc2a1abd36e9525313d5cd408"},{"name":"https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst","tags":["x_refsource_MISC"],"url":"https://github.com/pyca/pyopenssl/blob/358cbf29c4e364c59930e53a270116249581eaa3/CHANGELOG.rst"}],"affected":[{"vendor":"pyca","product":"pyopenssl","versions":[{"version":">= 22.0.0, < 26.0.0","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-03-17T23:34:28.483Z"},"descriptions":[{"lang":"en","value":"pyOpenSSL is a Python wrapper around the OpenSSL library. Starting in version 22.0.0 and prior to version 26.0.0, if a user provided callback to `set_cookie_generate_callback` returned a cookie value greater than 256 bytes, pyOpenSSL would overflow an OpenSSL provided buffer. Starting in version 26.0.0, cookie values that are too long are now rejected."}],"source":{"advisory":"GHSA-5pwr-322w-8jr4","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-03-18T19:52:08.536876Z","id":"CVE-2026-27459","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-03-18T19:52:15.812Z"}}]}}