{"id":"UBUNTU-CVE-2025-3891","details":"A flaw was found in the mod_auth_openidc module for Apache httpd. This flaw allows a remote, unauthenticated attacker to trigger a denial of service by sending an empty POST request when the OIDCPreservePost directive is enabled. The server crashes consistently, affecting availability.","modified":"2026-05-20T16:22:21.377595670Z","published":"2025-04-29T12:15:00Z","upstream":["CVE-2025-3891"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2025-3891"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2025-3891"},{"type":"REPORT","url":"https://access.redhat.com/security/cve/CVE-2025-3891"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2361633"}],"affected":[{"package":{"name":"libapache2-mod-auth-openidc","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/libapache2-mod-auth-openidc?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6.0-1","1.8.5-1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.8.5-1","binary_name":"libapache2-mod-auth-openidc"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-3891.json"}},{"package":{"name":"libapache2-mod-auth-openidc","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/libapache2-mod-auth-openidc?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1.6-1","2.3.1-2","2.3.2-1","2.3.2-1build1","2.3.3-1build1"],"ecosystem_specific":{"binaries":[{"binary_name":"libapache2-mod-auth-openidc","binary_version":"2.3.3-1build1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-3891.json"}},{"package":{"name":"libapache2-mod-auth-openidc","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/libapache2-mod-auth-openidc?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.3.10.2-1","2.4.0.4-1","2.4.1-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libapache2-mod-auth-openidc","binary_version":"2.4.1-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-3891.json"}},{"package":{"name":"libapache2-mod-auth-openidc","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/libapache2-mod-auth-openidc?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.4.9-1","2.4.9.4-1","2.4.10-1","2.4.10-1build1","2.4.11-1","2.4.11-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libapache2-mod-auth-openidc","binary_version":"2.4.11-1ubuntu0.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-3891.json"}},{"package":{"name":"libapache2-mod-auth-openidc","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/libapache2-mod-auth-openidc?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.4.14.2-1","2.4.14.4-2","2.4.14.4-2build1","2.4.15.1-1","2.4.15.1-1build2","2.4.15.1-1build3","2.4.15.1-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.4.15.1-1ubuntu0.1","binary_name":"libapache2-mod-auth-openidc"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-3891.json"}},{"package":{"name":"libapache2-mod-auth-openidc","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/libapache2-mod-auth-openidc?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.4.16.10-1","2.4.17-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libapache2-mod-auth-openidc","binary_version":"2.4.17-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-3891.json"}},{"package":{"name":"libapache2-mod-auth-openidc","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/libapache2-mod-auth-openidc?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.4.17-1","2.4.18.1-1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.4.18.1-1","binary_name":"libapache2-mod-auth-openidc"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-3891.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}