Vulnerability · Published Oct 1, 2026 · Assigned by apache

CVE-2026-73636Apache HTTP Server: mod_auth_digest one-time-nonce replay attack

High 8.1

In plain English

A high-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 0.4% (higher than 34% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.1High
Exploit odds (30 days)0.4%top 65.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:10httpd2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:8httpd2.4.37-65.module_el8.10.0+4332+2bef2e0d.13ALSA-2026:92616
AlmaLinux:9httpd2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:10httpd-core2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:9httpd-core2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:10httpd-devel2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:8httpd-devel2.4.37-65.module_el8.10.0+4332+2bef2e0d.13ALSA-2026:92616
AlmaLinux:9httpd-devel2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:10httpd-filesystem2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:8httpd-filesystem2.4.37-65.module_el8.10.0+4332+2bef2e0d.13ALSA-2026:92616
AlmaLinux:9httpd-filesystem2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:10httpd-manual2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:8httpd-manual2.4.37-65.module_el8.10.0+4332+2bef2e0d.13ALSA-2026:92616
AlmaLinux:9httpd-manual2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:10httpd-tools2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:8httpd-tools2.4.37-65.module_el8.10.0+4332+2bef2e0d.13ALSA-2026:92616
AlmaLinux:9httpd-tools2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:8mod_http21.15.7-10.module_el8.10.0+4233+8b7d9181.7ALSA-2026:92616
AlmaLinux:8mod_http21.15.7-10.module_el8.10.0+4270+e5f13fdb.7ALSA-2026:92616
AlmaLinux:10mod_ldap2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:8mod_ldap2.4.37-65.module_el8.10.0+4332+2bef2e0d.13ALSA-2026:92616
AlmaLinux:9mod_ldap2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:10mod_lua2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:9mod_lua2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:8mod_md1:2.0.8-8.module_el8.10.0+4295+280de5aa.4ALSA-2026:92616
AlmaLinux:10mod_proxy_html1:2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:8mod_proxy_html1:2.4.37-65.module_el8.10.0+4332+2bef2e0d.13ALSA-2026:92616
AlmaLinux:9mod_proxy_html1:2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:10mod_session2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:8mod_session2.4.37-65.module_el8.10.0+4332+2bef2e0d.13ALSA-2026:92616
AlmaLinux:9mod_session2.4.62-13.el9_8.9ALSA-2026:88229
AlmaLinux:10mod_ssl1:2.4.63-13.el10_2.8ALSA-2026:89860
AlmaLinux:8mod_ssl1:2.4.37-65.module_el8.10.0+4332+2bef2e0d.13ALSA-2026:92616
AlmaLinux:9mod_ssl1:2.4.62-13.el9_8.9ALSA-2026:88229
Alpine:v3.21apache22.4.69-r0ALPINE-CVE-2026-73636
Alpine:v3.22apache22.4.69-r0ALPINE-CVE-2026-73636
Alpine:v3.23apache22.4.69-r0ALPINE-CVE-2026-73636
Alpine:v3.24apache22.4.69-r0ALPINE-CVE-2026-73636
Debian:12apache2no fix listedDEBIAN-CVE-2026-73636
Debian:13apache22.4.69-1~deb13u1DEBIAN-CVE-2026-73636
Debian:14apache22.4.69-1DEBIAN-CVE-2026-73636
Rocky Linux:10httpd0:2.4.63-13.el10_2.8RLSA-2026:89860
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+1830+22f0c9e0RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+40197+0231e209.8RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+1842+4a9649e8.2RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+1938+3b7755d4.3RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+40206+be2c8a50.8RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+40257+286895ef.9RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+1984+1bed3124.4RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+40312+2c72bb9b.10RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+2061+8d03fdec.5RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+40402+af9563a3.13RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+40045+6ce8579b.6RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+40053+5a18018e.7RLSA-2026:92616
Rocky Linux:8httpd0:2.4.37-65.module+el8.10.0+1840+b070a976.1RLSA-2026:92616
Rocky Linux:9httpd0:2.4.62-13.el9_8.9RLSA-2026:88229
Rocky Linux:8mod_http20:1.15.7-10.module+el8.10.0+40257+286895ef.7RLSA-2026:92616
Rocky Linux:8mod_http20:1.15.7-10.module+el8.10.0+40204+716978aa.6RLSA-2026:92616
Rocky Linux:8mod_http20:1.15.7-10.module+el8.10.0+40197+0231e209.5RLSA-2026:92616
Rocky Linux:8mod_http20:1.15.7-10.module+el8.10.0+2061+8d03fdec.4RLSA-2026:92616
Rocky Linux:8mod_http20:1.15.7-10.module+el8.10.0+1938+3b7755d4.3RLSA-2026:92616
Rocky Linux:8mod_http20:1.15.7-10.module+el8.10.0+1883+38ed6c58.1RLSA-2026:92616
Rocky Linux:8mod_http20:1.15.7-10.module+el8.10.0+1830+22f0c9e0RLSA-2026:92616
Rocky Linux:8mod_http20:1.15.7-10.module+el8.10.0+1775+6b057638RLSA-2026:92616
Rocky Linux:8mod_md1:2.0.8-8.module+el8.10.0+40053+5a18018e.2RLSA-2026:92616
Rocky Linux:8mod_md1:2.0.8-8.module+el8.9.0+1370+89cc8ad5RLSA-2026:92616
Rocky Linux:8mod_md1:2.0.8-8.module+el8.10.0+40369+03c444c1.4RLSA-2026:92616
Ubuntu:22.04:LTSapache22.4.52-1ubuntu4.25USN-8931-1
Ubuntu:22.04:LTSapache22.4.52-1ubuntu4.25UBUNTU-CVE-2026-73636
Ubuntu:24.04:LTSapache22.4.58-1ubuntu8.17USN-8931-1
Ubuntu:24.04:LTSapache22.4.58-1ubuntu8.17UBUNTU-CVE-2026-73636
Ubuntu:26.04:LTSapache22.4.66-2ubuntu2.6UBUNTU-CVE-2026-73636
Ubuntu:26.04:LTSapache22.4.66-2ubuntu2.6USN-8931-1
Ubuntu:26.10apache2no fix listedUBUNTU-CVE-2026-73636

Affected products (as reported)

VendorProductVersions
Apache Software Foundation Apache HTTP Server 2.4.0 – through 2.4.68

Weakness: CWE-294 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References