CVE-2025-3891Mod_auth_openidc: dos via empty post in mod_auth_openidc with oidcpreservepost enabled
- 7.5HighCVSS base score
- 1.6%Exploitation in 30 daysEPSS · top 24% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By redhat
- 6 days later
· 6 days later
Published
- 18 months later
· 18 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| redhatCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 1.6% · top 24% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Affected products
mod_auth_openidc
- affected 2.0.0 – < 2.4.13.1
Red Hat · Red Hat Enterprise Linux 8
- unaffected 8100020250426100353.489197e6 – < *
Red Hat · Red Hat Enterprise Linux 8.2 Advanced Update Support
- unaffected 8020020250612174445.4cda2c84 – < *
Red Hat · Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
- unaffected 8040020250618101351.522a0ee4 – < *
Red Hat · Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
- unaffected 8060020250617090503.ad008a3a – < *
Red Hat · Red Hat Enterprise Linux 8.6 Telecommunications Update Service
- unaffected 8060020250617090503.ad008a3a – < *
Red Hat · Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions
- unaffected 8060020250617090503.ad008a3a – < *
Red Hat · Red Hat Enterprise Linux 8.8 Telecommunications Update Service
- unaffected 8080020250617090716.63b34585 – < *
Red Hat · Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
- unaffected 8080020250617090716.63b34585 – < *
Red Hat · Red Hat Enterprise Linux 9
- unaffected 0:2.4.10-1.el9_6.2 – < *
Red Hat · Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions
- unaffected 0:2.4.9.4-1.el9_0.3 – < *
Red Hat · Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions
- unaffected 0:2.4.9.4-1.el9_2.3 – < *
Red Hat · Red Hat Enterprise Linux 9.4 Extended Update Support
- unaffected 0:2.4.9.4-4.el9_4.2 – < *
Red Hat · Red Hat Enterprise Linux 10
All versions: affected
Red Hat · Red Hat Enterprise Linux 7
All versions: unaffected
References
References14
- RHSA-2025:10002 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2025:10003 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2025:10004 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2025:10006 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2025:10007 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2025:10008 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2025:10010 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2025:4597 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- RHSA-2025:9396 (opens in a new tab)vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2025-3891 (opens in a new tab)vdb-entryx_refsource_REDHAT
- RHBZ#2361633 (opens in a new tab)issue-trackingx_refsource_REDHAT
- https://github.com/OpenIDC/mod_auth_openidc/commit/6a0b5f66c87184dfe0e4400f6bdd46a82dc0ec2b (opens in a new tab)
- https://github.com/OpenIDC/mod_auth_openidc/security/advisories/GHSA-x7cf-8wgv-5j86 (opens in a new tab)
- https://lists.debian.org/debian-lts-announce/2025/05/msg00007.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-13653 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-3891)Record last updated .