Vulnerability · Published Jun 8, 2026 · Assigned by apache
CVE-2026-44631Apache HTTP Server: Heap Underflow in `ap_regname` via Signed Char Overflow
Critical 9.8
In plain English
A critical-severity security flaw in Apache HTTP Server from Apache Software Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)9.8Critical
Exploit odds (30 days)0.5%top 56.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Buffer Underwrite vulnerability in Apache HTTP Server on crafted regular expressions in the configuration. This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:10 | httpd | 2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:8 | httpd | 2.4.37-65.module_el8.10.0+4233+8b7d9181.9 | ALSA-2026:42828 |
| AlmaLinux:9 | httpd | 2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:10 | httpd-core | 2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:9 | httpd-core | 2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:10 | httpd-devel | 2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:8 | httpd-devel | 2.4.37-65.module_el8.10.0+4233+8b7d9181.9 | ALSA-2026:42828 |
| AlmaLinux:9 | httpd-devel | 2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:10 | httpd-filesystem | 2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:9 | httpd-filesystem | 2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:10 | httpd-manual | 2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:8 | httpd-manual | 2.4.37-65.module_el8.10.0+4233+8b7d9181.9 | ALSA-2026:42828 |
| AlmaLinux:9 | httpd-manual | 2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:10 | httpd-tools | 2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:8 | httpd-tools | 2.4.37-65.module_el8.10.0+4233+8b7d9181.9 | ALSA-2026:42828 |
| AlmaLinux:9 | httpd-tools | 2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:8 | mod_http2 | 1.15.7-10.module_el8.10.0+4233+8b7d9181.7 | ALSA-2026:42828 |
| AlmaLinux:10 | mod_ldap | 2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:8 | mod_ldap | 2.4.37-65.module_el8.10.0+4233+8b7d9181.9 | ALSA-2026:42828 |
| AlmaLinux:9 | mod_ldap | 2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:10 | mod_lua | 2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:9 | mod_lua | 2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:8 | mod_md | 1:2.0.8-8.module_el8.10.0+4088+57f011c1.2 | ALSA-2026:42828 |
| AlmaLinux:10 | mod_proxy_html | 1:2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:8 | mod_proxy_html | 1:2.4.37-65.module_el8.10.0+4233+8b7d9181.9 | ALSA-2026:42828 |
| AlmaLinux:9 | mod_proxy_html | 1:2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:10 | mod_session | 2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:8 | mod_session | 2.4.37-65.module_el8.10.0+4233+8b7d9181.9 | ALSA-2026:42828 |
| AlmaLinux:9 | mod_session | 2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| AlmaLinux:10 | mod_ssl | 1:2.4.63-13.el10_2.4 | ALSA-2026:34109 |
| AlmaLinux:8 | mod_ssl | 1:2.4.37-65.module_el8.10.0+4233+8b7d9181.9 | ALSA-2026:42828 |
| AlmaLinux:9 | mod_ssl | 1:2.4.62-13.el9_8.5 | ALSA-2026:41906 |
| Alpine:v3.21 | apache2 | 2.4.68-r0 | ALPINE-CVE-2026-44631 |
| Alpine:v3.22 | apache2 | 2.4.68-r0 | ALPINE-CVE-2026-44631 |
| Alpine:v3.23 | apache2 | 2.4.68-r0 | ALPINE-CVE-2026-44631 |
| Alpine:v3.24 | apache2 | 2.4.68-r0 | ALPINE-CVE-2026-44631 |
| Debian:12 | apache2 | 2.4.68-1~deb12u1 | DEBIAN-CVE-2026-44631 |
| Debian:13 | apache2 | 2.4.68-1~deb13u1 | DEBIAN-CVE-2026-44631 |
| Debian:14 | apache2 | 2.4.68-1 | DEBIAN-CVE-2026-44631 |
| Rocky Linux:10 | httpd | 0:2.4.63-13.el10_2.4 | RLSA-2026:34109 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+2061+8d03fdec.5 | RLSA-2026:42828 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+1984+1bed3124.4 | RLSA-2026:42828 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+1938+3b7755d4.3 | RLSA-2026:42828 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+40045+6ce8579b.6 | RLSA-2026:42828 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+40206+be2c8a50.8 | RLSA-2026:42828 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+40053+5a18018e.7 | RLSA-2026:42828 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+1830+22f0c9e0 | RLSA-2026:42828 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+1842+4a9649e8.2 | RLSA-2026:42828 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+1840+b070a976.1 | RLSA-2026:42828 |
| Rocky Linux:8 | httpd | 0:2.4.37-65.module+el8.10.0+40197+0231e209.8 | RLSA-2026:42828 |
| Rocky Linux:9 | httpd | 0:2.4.62-13.el9_8.5 | RLSA-2026:41906 |
| Rocky Linux:8 | mod_http2 | 0:1.15.7-10.module+el8.10.0+2061+8d03fdec.4 | RLSA-2026:42828 |
| Rocky Linux:8 | mod_http2 | 0:1.15.7-10.module+el8.10.0+1883+38ed6c58.1 | RLSA-2026:42828 |
| Rocky Linux:8 | mod_http2 | 0:1.15.7-10.module+el8.10.0+40197+0231e209.5 | RLSA-2026:42828 |
| Rocky Linux:8 | mod_http2 | 0:1.15.7-10.module+el8.10.0+1830+22f0c9e0 | RLSA-2026:42828 |
| Rocky Linux:8 | mod_http2 | 0:1.15.7-10.module+el8.10.0+1938+3b7755d4.3 | RLSA-2026:42828 |
| Rocky Linux:8 | mod_http2 | 0:1.15.7-10.module+el8.10.0+1775+6b057638 | RLSA-2026:42828 |
| Rocky Linux:8 | mod_http2 | 0:1.15.7-10.module+el8.10.0+40204+716978aa.6 | RLSA-2026:42828 |
| Rocky Linux:8 | mod_md | 1:2.0.8-8.module+el8.9.0+1370+89cc8ad5 | RLSA-2026:42828 |
| Rocky Linux:8 | mod_md | 1:2.0.8-8.module+el8.10.0+40053+5a18018e.2 | RLSA-2026:42828 |
| Ubuntu:22.04:LTS | apache2 | 2.4.52-1ubuntu4.23 | USN-8516-1 |
| Ubuntu:22.04:LTS | apache2 | 2.4.52-1ubuntu4.23 | UBUNTU-CVE-2026-44631 |
| Ubuntu:24.04:LTS | apache2 | 2.4.58-1ubuntu8.15 | UBUNTU-CVE-2026-44631 |
| Ubuntu:24.04:LTS | apache2 | 2.4.58-1ubuntu8.15 | USN-8516-1 |
| Ubuntu:25.10 | apache2 | no fix listed | UBUNTU-CVE-2026-44631 |
| Ubuntu:26.04:LTS | apache2 | 2.4.66-2ubuntu2.4 | USN-8516-1 |
| Ubuntu:26.04:LTS | apache2 | 2.4.66-2ubuntu2.4 | UBUNTU-CVE-2026-44631 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Apache Software Foundation | Apache HTTP Server | 2.4.0 – through 2.4.67 |
Weakness: CWE-124 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H