Red Hat Security Advisory: httpd:2.4 security update
🔗 CVE IDs covered (7)
📋 Description
CVE-2025-53020 — mod_http2: Apache HTTP Server: HTTP/2 DoS by Memory Increase CVE-2026-28780 — Apache HTTP Server: mod_proxy_ajp: Apache HTTP Server mod_proxy_ajp: Arbitrary code execution via heap-based buffer overflow CVE-2026-33007 — httpd: mod_authn_socache: NULL pointer dereference can cause a child process crash CVE-2026-33857 — httpd: mod_proxy_ajp: off-by-one out-of-bounds reads in AJP getter functions CVE-2026-34032 — httpd: mod_proxy_ajp: heap-based buffer over-read due to missing null-termination check CVE-2026-34059 — httpd: mod_proxy_ajp: heap-based buffer over-read and memory disclosure in ajp_parse_data() CVE-2026-49975 — httpd: httpd: HTTP/2 Remote Denial of Service via compression bomb and Slowloris-style attack
🎯 Affected products52
- Red Hat Enterprise Linux AppStream AUS (v.8.6)
- Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- httpd-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.src (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- httpd-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.src (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- httpd-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- httpd-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- httpd-debuginfo-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- httpd-debuginfo-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- httpd-debugsource-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- httpd-debugsource-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- httpd-devel-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- httpd-devel-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- httpd-filesystem-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.noarch (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- httpd-filesystem-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.noarch (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- httpd-manual-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.noarch (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- httpd-manual-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.noarch (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- httpd-tools-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- httpd-tools-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- httpd-tools-debuginfo-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- httpd-tools-debuginfo-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- mod_http2-0:1.15.7-5.module+el8.6.0+24496+af8fe930.5.src (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- mod_http2-0:1.15.7-5.module+el8.6.0+24496+af8fe930.5.src (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- mod_http2-0:1.15.7-5.module+el8.6.0+24496+af8fe930.5.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- mod_http2-0:1.15.7-5.module+el8.6.0+24496+af8fe930.5.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- mod_http2-debuginfo-0:1.15.7-5.module+el8.6.0+24496+af8fe930.5.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- mod_http2-debuginfo-0:1.15.7-5.module+el8.6.0+24496+af8fe930.5.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- mod_http2-debugsource-0:1.15.7-5.module+el8.6.0+24496+af8fe930.5.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- mod_http2-debugsource-0:1.15.7-5.module+el8.6.0+24496+af8fe930.5.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- mod_ldap-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream AUS (v.8.6)
- mod_ldap-0:2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64 (httpd:2.4) as a component of Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
- +22 more not shown
✅ Remediation
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: The attack surface can be reduced by disabling HTTP/2 support in Apache. Follow the guidance in Red Hat KCS article to: - Remove h2 and h2c from the Protocols directive - Disable mod_http2 and mod_proxy_http2 modules (if not required) https://access.redhat.com/node/7056356 Workaround: Disabling mod_authn_socache and restarting httpd will mitigate this flaw. Workaround: Disabling mod_proxy_ajp and restarting httpd will mitigate this flaw. Workaround: See the security bulletin for a detailed mitigation procedure.
🔗 References (10)
- selfhttps://access.redhat.com/errata/RHSA-2026:36831
- externalhttps://access.redhat.com/security/updates/classification/#important
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2379343
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2464940
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2464952
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2464953
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2465299
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2466913
- externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2485371
- selfhttps://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_36831.json