{"id":"UBUNTU-CVE-2026-124040","details":"CivetWeb through 1.16, when built with USE_HTTP2 and enable_http2 on, contains a use-after-free vulnerability in handle_http2() that retains freed :method and :path pointers. Unauthenticated remote attackers can send a later HEADERS frame omitting these pseudo-headers to influence request method or path seen by access rules, or crash the server.","modified":"2026-11-10T02:50:22.511615335Z","published":"2026-11-09T00:00:00Z","upstream":["CVE-2026-124040"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-124040"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-124040"},{"type":"REPORT","url":"https://github.com/civetweb/civetweb/issues/1379"},{"type":"REPORT","url":"https://github.com/civetweb/civetweb"},{"type":"REPORT","url":"https://github.com/civetweb/civetweb/blob/v1.16/src/http2.inl#L1574-L1581"},{"type":"REPORT","url":"https://www.vulncheck.com/advisories/civetweb-through-1.16-http-2-use-after-free-via-stale-pseudo-header-state"}],"affected":[{"package":{"name":"civetweb","ecosystem":"Ubuntu:Pro:22.04:LTS","purl":"pkg:deb/ubuntu/civetweb?arch=source&distro=esm-apps%2Fjammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.13+dfsg-5","1.15+dfsg-1","1.15+dfsg-3","1.15+dfsg-3ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"civetweb","binary_version":"1.15+dfsg-3ubuntu0.1~esm1"},{"binary_name":"libcivetweb1","binary_version":"1.15+dfsg-3ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-124040.json"}},{"package":{"name":"civetweb","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/civetweb?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.16+dfsg-1","1.16+dfsg-1build1","1.16+dfsg-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"civetweb","binary_version":"1.16+dfsg-1ubuntu0.1"},{"binary_version":"1.16+dfsg-1ubuntu0.1","binary_name":"libcivetweb1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-124040.json"}},{"package":{"name":"civetweb","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/civetweb?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.16+dfsg-3","1.16+dfsg-4"],"ecosystem_specific":{"binaries":[{"binary_name":"civetweb","binary_version":"1.16+dfsg-4"},{"binary_name":"libcivetweb1","binary_version":"1.16+dfsg-4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-124040.json"}},{"package":{"name":"civetweb","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/civetweb?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.16+dfsg-2","1.16+dfsg-3","1.16+dfsg-3ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"civetweb","binary_version":"1.16+dfsg-3ubuntu0.1"},{"binary_version":"1.16+dfsg-3ubuntu0.1","binary_name":"libcivetweb1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-124040.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"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"},{"type":"Ubuntu","score":"medium"}]}