An integer overflow in the case of failed ACME certificate renewal leads, after a number of failures (~30 days in default configurations), to the backoff timer becoming 0. Attempts to renew the certificate then are repeated without delays until it succeeds.
This issue affects Apache HTTP Server: from 2.4.30 before 2.4.66.
Users are recommended to upgrade to version 2.4.66, which fixes the issue.
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alma_linux | — | Upgrade mod_mdUpgrade httpdUpgrade mod_proxy_htmlUpgrade httpd-manualUpgrade httpd-develUpgrade mod_sslUpgrade mod_sessionUpgrade mod_http2Upgrade httpd-toolsUpgrade mod_ldapUpgrade httpd-filesystem | Dec 23, 2025 | Dec 22, 2025 |
| Alpine Linux | — | Upgrade apache2 | Dec 8, 2025 | Dec 5, 2025 |
| Amazon Linux Ami 2 | — | Upgrade httpdUpgrade httpd-filesystemUpgrade mod_ldapUpgrade httpd-debuginfoUpgrade mod_mdUpgrade mod_sslUpgrade httpd-develUpgrade httpd-manualUpgrade mod_sessionUpgrade httpd-toolsUpgrade mod_proxy_html | May 20, 2026 | May 20, 2026 |
| Apache Httpd | — | Upgrade to the latest version of Apache HTTPD | Dec 8, 2025 | Dec 5, 2025 |
| Apple Osx Apache | — | Upgrade macOS to the latest version | Mar 27, 2026 | Mar 24, 2026 |
| Debian | — | Upgrade apache2 | Jan 12, 2026 | Jan 12, 2026 |
| Freebsd | — | Upgrade apache24 | Dec 10, 2025 | Dec 4, 2025 |
| Gentoo Linux | — | Upgrade www-servers/apache. | Aug 16, 2026 | Aug 13, 2026 |
| Oracle_linux | — | Upgrade httpd-develUpgrade mod_sessionUpgrade httpd-filesystemUpgrade mod_sslUpgrade mod_mdUpgrade httpdUpgrade httpd-manualUpgrade mod_proxy_htmlUpgrade httpd-toolsUpgrade mod_http2Upgrade mod_ldap | Dec 24, 2025 | Dec 5, 2025 |
| Redhat_linux | — | Upgrade mod_ldap-debuginfoUpgrade mod_http2-debugsourceUpgrade mod_ldapUpgrade mod_http2Upgrade mod_proxy_htmlUpgrade mod_proxy_html-debuginfoUpgrade httpd-manualUpgrade mod_ssl-debuginfoUpgrade httpd-toolsUpgrade mod_md-debugsourceUpgrade mod_sessionUpgrade mod_session-debuginfoUpgrade mod_md-debuginfoUpgrade mod_http2-debuginfoUpgrade mod_mdUpgrade httpd-debuginfoUpgrade httpd-debugsourceUpgrade httpd-filesystemUpgrade httpdUpgrade mod_sslUpgrade httpd-develUpgrade httpd-tools-debuginfo | Dec 23, 2025 | Dec 5, 2025 |
| Rocky_linux | — | Upgrade httpdUpgrade mod_md-debugsourceUpgrade httpd-tools-debuginfoUpgrade mod_http2-debugsourceUpgrade httpd-toolsUpgrade mod_mdUpgrade mod_ssl-debuginfoUpgrade mod_http2-debuginfoUpgrade httpd-develUpgrade mod_http2Upgrade mod_md-debuginfoUpgrade mod_ldap-debuginfoUpgrade mod_session-debuginfoUpgrade httpd-debugsourceUpgrade mod_sslUpgrade mod_proxy_html-debuginfoUpgrade httpd-debuginfoUpgrade mod_sessionUpgrade mod_proxy_htmlUpgrade mod_ldap | Feb 5, 2026 | Dec 23, 2025 |
| Suse | — | Upgrade apache2-example-pagesUpgrade apache2-develUpgrade apache2-tls13-workerUpgrade apache2-tls13-utilsUpgrade apache2-workerUpgrade apache2-docUpgrade apache2-eventUpgrade apache2-tls13-develUpgrade apache2Upgrade apache2-tls13Upgrade apache2-tls13-preforkUpgrade apache2-manualUpgrade apache2-tls13-docUpgrade apache2-utilsUpgrade apache2-tls13-example-pagesUpgrade apache2-prefork | Apr 15, 2026 | Dec 23, 2025 |
| Ubuntu | — | Upgrade apache2Upgrade apache2 (Ubuntu Pro) | Jan 20, 2026 | Dec 5, 2025 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | Feb 9, 2026 | Dec 5, 2025 |
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