Apache HTTP Server: mod_auth_digest one-time-nonce replay attack
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 4 fixed, 2 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-294.
Summary
Authentication bypass by capture-replay in mod_auth_digest in Apache Software Foundation Apache HTTP Server 2.4.x on all platforms allows a man-in-the-middle (MITM) attacker to replay captured digest authentication credentials via crafted requests that trigger garbage collection of the client's shared memory entry when AuthDigestNonceLifetime is set to 0. Users are recommended to upgrade to version 2.4.69, which fixes this issue.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Red Hat 4 advisories
- RHSA-2026:92616 Released 2026-10-29 · Red Hat rating Importanthttpd:2.4 security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 8) httpd-2.4.37-65.module+el8.10.0+25092+6f3ea0dd.13.aarch64::httpd:2.4, httpd-2.4.37-65.module+el8.10.0+25092+6f3ea0dd.13.ppc64le::httpd:2.4, httpd-2.4.37-65.module+el8.10.0+25092+6f3ea0dd.13.s390x::httpd:2.4 +38
- RHSA-2026:89860 Released 2026-10-26 · Red Hat rating Importanthttpd security update
- Red Hat Enterprise Linux AppStream (v. 10) httpd-2.4.63-13.el10_2.8, httpd-core-2.4.63-13.el10_2.8, httpd-devel-2.4.63-13.el10_2.8 +8
- RHSA-2026:88229 Released 2026-10-22 · Red Hat rating Importanthttpd security update
- Red Hat Enterprise Linux AppStream (v. 9) httpd-2.4.62-13.el9_8.9, httpd-core-2.4.62-13.el9_8.9, httpd-devel-2.4.62-13.el9_8.9 +8
Show 1 more Red Hat advisories
- RHSA-2026:74858 Released 2026-10-02 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images httpd-2.4.69-1.hum1@aarch64, httpd-2.4.69-1.hum1@src, httpd-2.4.69-1.hum1@x86_64 +20
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 7 | Affected | No fix yet |
| Red Hat JBoss Core Services | Affected | No fix yet |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:89860 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:92616 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:88229 |
| Red Hat Hardened Images | Fixed | RHSA-2026:74858 |
Not affected: 1 product
- Red Hat Enterprise Linux 6
Timeline
- 2026-10-02 Threatist record created from CVE-2026-73636
- 2026-10-03 Alias added: GHSA-x3h4-7828-fv9v
- 2026-10-07 Affected versions changed · Red Hat
- 2026-10-23 Fix available: RHSA-2026:88229 · Red Hat
- 2026-10-23 Fix available: Red Hat Enterprise Linux AppStream (v. 9) · Red Hat
- 2026-10-26 Fix available: RHSA-2026:89860 · Red Hat
- 2026-10-26 Fix available: Red Hat Enterprise Linux AppStream (v. 10) · Red Hat
- 2026-10-30 Fix available: RHSA-2026:92616 · Red Hat
- 2026-10-30 Fix available: Red Hat Enterprise Linux AppStream (v. 8) · Red Hat
References
More Apache Http Server vulnerabilities
- TI-2021-18535 Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773) KEVCVSS 3.1CRITICAL 9.8
- TI-2021-18417 Path traversal and file disclosure vulnerability in Apache HTTP Server 2.4.49 KEVCVSS 3.1CRITICAL 9.8
- TI-2024-25716 Apache HTTP Server weakness in mod_rewrite when first segment of substitution matches filesystem path. KEVCVSS 3.1CRITICAL 9.1
- TI-2021-17490 mod_proxy SSRF KEVCVSS 3.1CRITICAL 9.0
- TI-2019-00184 Use after free in Apache HTTP Server KEVCVSS 3.1HIGH 7.8
- TI-2009-03392 The TLS protocol, and the SSL protocol 3.0 and possibly earlier, as used in Microsoft… CVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-73636 · CVE Program
- CVE-2026-73636 · NVD
- FIRST EPSS
- GHSA-x3h4-7828-fv9v · GitHub Advisory Database · CC BY 4.0
- CVE-2026-73636 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences