{"id":"CVE-2026-54789","title":"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","summary":"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…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-125","CWE-787"],"published":"2026-08-21","updated":"2026-09-18","sourceUpdated":"2026-09-18T20:09:01.757","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-54789","references":[{"url":"https://github.com/OpenIDC/mod_auth_openidc/commit/8017478471cc071c49aa073c5c9be652a73a8630","label":"security-advisories@github.com"},{"url":"https://github.com/OpenIDC/mod_auth_openidc/security/advisories/GHSA-vgr5-qcpp-x2pr","label":"security-advisories@github.com"},{"url":"https://lists.debian.org/debian-lts-announce/2026/09/msg00003.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54789.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-54789"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2521051"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-54789"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54789"},{"url":"https://access.redhat.com/errata/RHSA-2026:69715"},{"url":"https://access.redhat.com/errata/RHSA-2026:69719"},{"url":"https://access.redhat.com/errata/RHSA-2026:69712"},{"url":"https://access.redhat.com/errata/RHSA-2026:69713"},{"url":"https://access.redhat.com/errata/RHSA-2026:69717"},{"url":"https://access.redhat.com/errata/RHSA-2026:69720"},{"url":"https://access.redhat.com/errata/RHSA-2026:69718"},{"url":"https://access.redhat.com/errata/RHSA-2026:69716"}],"tags":["nvd","csaf","vex","red-hat"],"epss":0.00718,"epssPercentile":0.51776,"ingestedAt":"2026-09-18T20:51:25.654Z","vendor":"Red Hat","product":"Red Hat Enterprise Linux AppStream E4S (v.8.8)","affected":["enterprise_linux 10","enterprise_linux 8","enterprise_linux 9","enterprise_linux_server_v_7_els","enterprise_linux_appstream_eus_v_10_0","enterprise_linux_appstream_aus_v_8_4","enterprise_linux_appstream_eus_extension_v_8_4","enterprise_linux_appstream_aus_v_8_6","enterprise_linux_appstream_eus_extension_v_8_6","enterprise_linux_appstream_e4s_v_8_8","enterprise_linux_appstream_tus_v_8_8","enterprise_linux_appstream_e4s_v_9_2","enterprise_linux_appstream_e4s_v_9_4","enterprise_linux_appstream_eus_v_9_6"],"patched":["enterprise_linux_server_v_7_els","enterprise_linux_appstream_eus_v_10_0","enterprise_linux_appstream_aus_v_8_4","enterprise_linux_appstream_eus_extension_v_8_4","enterprise_linux_appstream_aus_v_8_6","enterprise_linux_appstream_eus_extension_v_8_6","enterprise_linux_appstream_e4s_v_8_8","enterprise_linux_appstream_tus_v_8_8","enterprise_linux_appstream_e4s_v_9_2","enterprise_linux_appstream_e4s_v_9_4","enterprise_linux_appstream_eus_v_9_6"],"slug":"CVE-2026-54789","body":"## Overview\n\nmod_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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **RHSA-2026:69715** · Red Hat · fixed in: Red Hat Enterprise Linux Server (v. 7 ELS) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:69715)\n- **RHSA-2026:69719** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:69719)\n- **RHSA-2026:69712** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:69712)\n- **RHSA-2026:69713** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:69713)\n- **RHSA-2026:69717** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:69717)\n- **RHSA-2026:69720** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.2) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:69720)\n- **RHSA-2026:69718** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:69718)\n- **RHSA-2026:69716** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6) · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:69716)\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-09-22 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54789.json)","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}