Apache HTTP Server: mod_dav_lock indirect lock crash
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 14 fixed, 1 without a fix
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-476.
Summary
A NULL pointer dereference in mod_dav_lock in Apache HTTP Server 2.4.66 and earlier may allow an attacker to crash the server with a malicious request.mod_dav_lock is not used internally by mod_dav or mod_dav_fs. The only known use-case for mod_dav_lock was mod_dav_svn from Apache Subversion earlier than version 1.2.0. Users are recommended to upgrade to version 2.4.66, which fixes this issue, or remove mod_dav_lock.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Red Hat 12 advisories
- RHSA-2026:92590 Released 2026-10-29 · Red Hat rating Importanthttpd security update
- Red Hat Enterprise Linux Server (v. 7 ELS) httpd-2.4.6-99.el7_9.8, mod_ssl-1:2.4.6-99.el7_9.8
- Red Hat Enterprise Linux Server Optional (v. 7 ELS) mod_proxy_html-1:2.4.6-99.el7_9.8
- RHSA-2026:67152 Released 2026-09-14 · Red Hat rating Importanthttpd security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) httpd-2.4.53-11.el9_2.15, httpd-core-2.4.53-11.el9_2.15, mod_ldap-2.4.53-11.el9_2.15 +2
- RHSA-2026:66323 Released 2026-09-10 · Red Hat rating Importanthttpd security update
- Red Hat Enterprise Linux AppStream E4S (v.9.4) httpd-2.4.57-11.el9_4.5, httpd-core-2.4.57-11.el9_4.5, mod_ldap-2.4.57-11.el9_4.5 +2
Show 9 more Red Hat advisories
- RHSA-2026:62165 Released 2026-09-01 · Red Hat rating Importanthttpd security update
- Red Hat Enterprise Linux AppStream EUS (v.9.6) httpd-2.4.62-4.el9_6.6, httpd-core-2.4.62-4.el9_6.6, httpd-devel-2.4.62-4.el9_6.6 +8
- RHSA-2026:53371 Released 2026-08-11 · Red Hat rating ImportantInsights proxy Container Image
- Red Hat Insights proxy 1.5 registry.redhat.io/insights-proxy/insights-proxy-container-rhel9
- RHSA-2026:47046 Released 2026-07-28 · Red Hat rating Importanthttpd security update
- Red Hat Enterprise Linux AppStream EUS (v. 10.0) httpd-2.4.63-1.el10_0.4, httpd-core-2.4.63-1.el10_0.4, httpd-devel-2.4.63-1.el10_0.4 +8
- RHSA-2026:42828 Released 2026-07-21 · 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+24521+219dcfc5.9.aarch64::httpd:2.4, httpd-2.4.37-65.module+el8.10.0+24521+219dcfc5.9.ppc64le::httpd:2.4, httpd-2.4.37-65.module+el8.10.0+24521+219dcfc5.9.s390x::httpd:2.4 +38
- RHSA-2026:41906 Released 2026-07-20 · Red Hat rating Importanthttpd security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) httpd-2.4.62-13.el9_8.5, httpd-core-2.4.62-13.el9_8.5, httpd-devel-2.4.62-13.el9_8.5 +8
- RHSA-2026:34109 Released 2026-07-01 · Red Hat rating Importanthttpd security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 10) httpd-2.4.63-13.el10_2.4, httpd-core-2.4.63-13.el10_2.4, httpd-devel-2.4.63-13.el10_2.4 +8
- RHSA-2026:27200 Released 2026-06-22 · Red Hat rating ImportantRed Hat JBoss Core Services Apache HTTP Server 2.4.62 SP4 security update
- Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-httpd-2.4.62-13.el7jbcs, jbcs-httpd24-httpd-devel-2.4.62-13.el7jbcs, jbcs-httpd24-httpd-manual-2.4.62-13.el7jbcs +10
- Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-httpd-2.4.62-13.el8jbcs, jbcs-httpd24-httpd-devel-2.4.62-13.el8jbcs, jbcs-httpd24-httpd-manual-2.4.62-13.el8jbcs +10
- RHSA-2026:27201 Released 2026-06-22 · Red Hat rating ImportantRed Hat JBoss Core Services Apache HTTP Server 2.4.62 SP4 security update
- Red Hat JBoss Core Services 2.4.62.SP4
- RHSA-2026:17080 Released 2026-05-13 · Red Hat rating ModerateRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images httpd-2.4.67-1.hum1@aarch64, httpd-2.4.67-1.hum1@src, httpd-2.4.67-1.hum1@x86_64 +10
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix yet |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:34109 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:42828 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:41906 |
| Red Hat Enterprise Linux AppStream E4S (v.9.2) | Fixed | RHSA-2026:67152 |
| Red Hat Enterprise Linux AppStream E4S (v.9.4) | Fixed | RHSA-2026:66323 |
| Red Hat Enterprise Linux AppStream EUS (v. 10.0) | Fixed | RHSA-2026:47046 |
| Red Hat Enterprise Linux AppStream EUS (v.9.6) | Fixed | RHSA-2026:62165 |
| Red Hat Enterprise Linux Server (v. 7 ELS) | Fixed | RHSA-2026:92590 |
| Red Hat Enterprise Linux Server Optional (v. 7 ELS) | Fixed | RHSA-2026:92590 |
| Red Hat Hardened Images | Fixed | RHSA-2026:17080 |
| Red Hat Insights proxy 1.5 | Fixed | RHSA-2026:53371 |
| Red Hat JBoss Core Services 2.4.62.SP4 | Fixed | RHSA-2026:27201 |
| Red Hat JBoss Core Services on RHEL 7 Server | Fixed | RHSA-2026:27200 |
| Red Hat JBoss Core Services on RHEL 8 | Fixed | RHSA-2026:27200 |
Not affected: 7 products
- Red Hat Enterprise Linux AppStream E4S (v.9.2)
- Red Hat Enterprise Linux AppStream E4S (v.9.4)
- Red Hat Enterprise Linux Server (v. 7 ELS)
- Red Hat Enterprise Linux Server Optional (v. 7 ELS)
- Red Hat Hardened Images
- Red Hat JBoss Core Services on RHEL 7 Server
- Red Hat JBoss Core Services on RHEL 8
Timeline
- 2026-10-02 Threatist record created from CVE-2026-29169
- 2026-10-03 Alias added: GHSA-jmv5-rcpx-7f7r
- 2026-10-09 Fix available: RHSA-2026:27201 · Red Hat
- 2026-10-09 Fix available: Red Hat JBoss Core Services 2.4.62.SP4 · Red Hat
- 2026-10-25 EPSS moved to the below the 50th percentile
- 2026-10-30 Fix available: RHSA-2026:92590 · Red Hat
- 2026-10-30 Fix available: Red Hat Enterprise Linux Server (v. 7 ELS), Red Hat Enterprise Linux Server Optional (v. 7 ELS) · 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-2026-29169 · CVE Program
- CVE-2026-29169 · NVD
- FIRST EPSS
- GHSA-jmv5-rcpx-7f7r · GitHub Advisory Database · CC BY 4.0
- CVE-2026-29169 · 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