Description
Heap-based Buffer Overflow vulnerability in mod_proxy_ajp of Apache HTTP Server. If mod_proxy_ajp connects to a malicious AJP server this AJP server can send a malicious AJP message back to mod_proxy_ajp and cause it to write 4 attacker controlled bytes after the end of a heap based buffer. This issue affects Apache HTTP Server: through 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.
Affected products
apache: http server
References10
- httpd.apache.org/security/vulnerabilities_24.html Release NotesVendor Advisory
- www.openwall.com/lists/oss-security/2026/05/05/9 Mailing ListThird Party Advisory
- access.redhat.com/errata/RHSA-2026:21391
- access.redhat.com/errata/RHSA-2026:21433
- access.redhat.com/errata/RHSA-2026:22140
- access.redhat.com/errata/RHSA-2026:27200
- access.redhat.com/errata/RHSA-2026:27201
- access.redhat.com/errata/RHSA-2026:36373
- access.redhat.com/errata/RHSA-2026:36831
- access.redhat.com/errata/RHSA-2026:36846
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 72 · as of 13 November 2026
- CWE
- CWE-122CWE-787
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