{"id":"UBUNTU-CVE-2026-27459","details":"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.","modified":"2026-03-25T19:58:20.756645Z","published":"2026-03-18T00:00:00Z","related":["USN-8115-1"],"upstream":["CVE-2026-27459"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-27459"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-27459"},{"type":"REPORT","url":"https://github.com/pyca/pyopenssl/security/advisories/GHSA-5pwr-322w-8jr4"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8115-1"}],"affected":[{"package":{"name":"pyopenssl","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/pyopenssl@23.2.0-1ubuntu0.1?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"23.2.0-1ubuntu0.1"}]}],"versions":["23.0.0-1","23.2.0-1"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-openssl","binary_version":"23.2.0-1ubuntu0.1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-27459.json"}},{"package":{"name":"pyopenssl","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/pyopenssl@25.0.0-1ubuntu0.1?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"25.0.0-1ubuntu0.1"}]}],"versions":["25.0.0-1"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-openssl","binary_version":"25.0.0-1ubuntu0.1"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-27459.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"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"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}