Description
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.
Affected products
apache: http server
References3
- httpd.apache.org/security/vulnerabilities_24.html Vendor Advisory
- www.openwall.com/lists/oss-security/2026/05/04/20 Mailing ListThird Party Advisory
- www.openwall.com/lists/oss-security/2026/05/05/12
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 49 · as of 13 November 2026
- CWE
- CWE-476
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