{"id":"UBUNTU-CVE-2026-54789","details":"mod_auth_openidc is an OpenID Certified authentication and authorization module for the Apache 2.x HTTP server that implements the OpenID Connect Relying Party functionality. Prior to 2.4.19.4, an out-of-bounds read and a one-byte out-of-bounds write exist in the state-cookie parser of `mod_auth_openidc`. The issue is fixed in version 2.4.19.4 by stopping the scan at the string terminator so a value-less token is rejected. No in-product workarounds are available. As a stop-gap, an upstream reverse proxy or WAF that rejects or normalizes malformed `Cookie` headers (tokens lacking `=`) can reduce exposure, but upgrading is the recommended remediation.","modified":"2026-09-02T19:36:23.829618767Z","published":"2026-08-21T16:17:00Z","upstream":["CVE-2026-54789"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-54789"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-54789"},{"type":"REPORT","url":"https://github.com/OpenIDC/mod_auth_openidc/security/advisories/GHSA-vgr5-qcpp-x2pr"}],"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/2026/UBUNTU-CVE-2026-54789.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/2026/UBUNTU-CVE-2026-54789.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/2026/UBUNTU-CVE-2026-54789.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/2026/UBUNTU-CVE-2026-54789.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_name":"libapache2-mod-auth-openidc","binary_version":"2.4.15.1-1ubuntu0.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54789.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_name":"libapache2-mod-auth-openidc","binary_version":"2.4.18.1-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-54789.json"}}],"schema_version":"1.9.0","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":"Ubuntu","score":"medium"}]}