RHSA-2026:55930: Important: mod_http2 security update

- Issued: - 2026-08-18 - Updated: - 2026-08-18 RHSA-2026:55930 - Security Advisory Synopsis Important: mod_http2 security update Type/Severity Security Advisory: Important Red Hat Lightspeed patch analysis Identify and remediate systems affected by this advisory. Topic An update for mod_http2 is now available for Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. Description The mod_h2 Apache httpd module implements the HTTP2 protocol (h2+h2c) on top of libnghttp2 for httpd 2.4 servers. Security Fix(es): - mod_http2: Apache HTTP Server: HTTP/2 DoS by Memory Increase (CVE-2025-53020) - httpd: httpd: HTTP/2 Remote Denial of Service via compression bomb and Slowloris-style attack (CVE-2026-49975) - httpd: Apache HTTP Server: Out-of-bounds Read in mod_headers and mod_mime (CVE-2026-43951) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. Solution For details on how to apply this update, which includes the changes described in this advisory, refer to: Affected Products - Red Hat Enterprise Linux Server - AUS 9.2 x86_64 - Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.2 ppc64le - Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.2 x86_64 - Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.2 aarch64 - Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.2 s390x - Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.2 x86_64 - Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.2 aarch64 - Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 9.2 ppc64le - Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 9.2 s390x Fixes - BZ - 2379343 - CVE-2025-53020 mod_http2: Apache HTTP Server: HTTP/2 DoS by Memory Increase - BZ - 2485371 - CVE-2026-49975 httpd: httpd: HTTP/2 Remote Denial of Service via compression bomb and Slowloris-style attack - BZ - 2486415 - CVE-2026-43951 httpd: Apache HTTP Server: Out-of-bounds Read in mod_headers and mod_mime Red Hat Enterprise Linux Server - AUS 9.2 | SRPM | | |---|---| | mod_http2-1.15.19-4.el9_2.8.src.rpm | SHA-256: a24b907eb1bd41a5ac483259315e7c4baaced6d4177e9bfe718ba0a88efa11d9 | | x86_64 | | | mod_http2-1.15.19-4.el9_2.8.x86_64.rpm | SHA-256: 8809ca23bc7ad22b610e5c102b20798be638b3e007442e7e795e03e30e0ae160 | | mod_http2-debuginfo-1.15.19-4.el9_2.8.x86_64.rpm | SHA-256: 54aedd7d293aaae779c30efb24f29385885078b1ad1b46f3691a6ce7eb559540 | | mod_http2-debugsource-1.15.19-4.el9_2.8.x86_64.rpm | SHA-256: e29a5906304169455bbaab7d70841eeb583adafbc874c1f55d6b8d5cf6acd129 | Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.2 | SRPM | | |---|---| | mod_http2-1.15.19-4.el9_2.8.src.rpm | SHA-256: a24b907eb1bd41a5ac483259315e7c4baaced6d4177e9bfe718ba0a88efa11d9 | | ppc64le | | | mod_http2-1.15.19-4.el9_2.8.ppc64le.rpm | SHA-256: 996f183bb290415a33574fffefee193069f26378694cb1c1d9d28ce71e873a96 | | mod_http2-debuginfo-1.15.19-4.el9_2.8.ppc64le.rpm | SHA-256: c428e7bb27a0a4e87dd95910aca9d4a085213cbf9c1067f162c926f98ccb00fd | | mod_http2-debugsource-1.15.19-4.el9_2.8.ppc64le.rpm | SHA-256: 2a3370487f6c40c8e716797e4bf05e74fa30ccfbe1cee16dfe74d76d77d5af97 | Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.2 | SRPM | | |---|---| | mod_http2-1.15.19-4.el9_2.8.src.rpm | SHA-256: a24b907eb1bd41a5ac483259315e7c4baaced6d4177e9bfe718ba0a88efa11d9 | | x86_64 | | | mod_http2-1.15.19-4.el9_2.8.x86_64.rpm | SHA-256: 8809ca23bc7ad22b610e5c102b20798be638b3e007442e7e795e03e30e0ae160 | | mod_http2-debuginfo-1.15.19-4.el9_2.8.x86_64.rpm | SHA-256: 54aedd7d293aaae779c30efb24f29385885078b1ad1b46f3691a6ce7eb559540 | | mod_http2-debugsource-1.15.19-4.el9_2.8.x86_64.rpm | SHA-256: e29a5906304169455bbaab7d70841eeb583adafbc874c1f55d6b8d5cf6acd129 | Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.2 | SRPM | | |---|---| | mod_http2-1.15.19-4.el9_2.8.src.rpm | SHA-256: a24b907eb1bd41a5ac483259315e7c4baaced6d4177e9bfe718ba0a88efa11d9 | | aarch64 | | | mod_http2-1.15.19-4.el9_2.8.aarch64.rpm | SHA-256: b7a60698bc56e5a350b56875b76e591457d4ec74cc363233e8ca2de335839898 | | mod_http2-debuginfo-1.15.19-4.el9_2.8.aarch64.rpm | SHA-256: 31eda13a997ad0cdcd2570b87c270835d236df8f07309d5dbe67d8c48eef781d | | mod_http2-debugsource-1.15.19-4.el9_2.8.aarch64.rpm | SHA-256: af4206f23a934931bfd9503f1b46f6f8070137eb754f4f7d988b004548b8b797 | Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.2 | SRPM | | |---|---| | mod_http2-1.15.19-4.el9_2.8.src.rpm | SHA-256: a24b907eb1bd41a5ac483259315e7c4baaced6d4177e9bfe718ba0a88efa11d9 | | s390x | | | mod_http2-1.15.19-4.el9_2.8.s390x.rpm | SHA-256: db2efc4f6acbfe234a5859188aec93c9a1bedf9911fa86e6c5880e31aa6a6e5c | | mod_http2-debuginfo-1.15.19-4.el9_2.8.s390x.rpm | SHA-256: 8f9148749feab3879d916df984d98233fef19e201406acaa57d804e7bd2456da | | mod_http2-debugsource-1.15.19-4.el9_2.8.s390x.rpm | SHA-256: 836f975a6688fec7f3e18087104cea601790b426054341779c6b37d8bf4c6bc7 | Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.2 | SRPM | | |---|---| | mod_http2-1.15.19-4.el9_2.8.src.rpm | SHA-256: a24b907eb1bd41a5ac483259315e7c4baaced6d4177e9bfe718ba0a88efa11d9 | | x86_64 | | | mod_http2-1.15.19-4.el9_2.8.x86_64.rpm | SHA-256: 8809ca23bc7ad22b610e5c102b20798be638b3e007442e7e795e03e30e0ae160 | | mod_http2-debuginfo-1.15.19-4.el9_2.8.x86_64.rpm | SHA-256: 54aedd7d293aaae779c30efb24f29385885078b1ad1b46f3691a6ce7eb559540 | | mod_http2-debugsource-1.15.19-4.el9_2.8.x86_64.rpm | SHA-256: e29a5906304169455bbaab7d70841eeb583adafbc874c1f55d6b8d5cf6acd129 | Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.2 | SRPM | | |---|---| | mod_http2-1.15.19-4.el9_2.8.src.rpm | SHA-256: a24b907eb1bd41a5ac483259315e7c4baaced6d4177e9bfe718ba0a88efa11d9 | | aarch64 | | | mod_http2-1.15.19-4.el9_2.8.aarch64.rpm | SHA-256: b7a60698bc56e5a350b56875b76e591457d4ec74cc363233e8ca2de335839898 | | mod_http2-debuginfo-1.15.19-4.el9_2.8.aarch64.rpm | SHA-256: 31eda13a997ad0cdcd2570b87c270835d236df8f07309d5dbe67d8c48eef781d | | mod_http2-debugsource-1.15.19-4.el9_2.8.aarch64.rpm | SHA-256: af4206f23a934931bfd9503f1b46f6f8070137eb754f4f7d988b004548b8b797 | Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 9.2 | SRPM | | |---|---| | mod_http2-1.15.19-4.el9_2.8.src.rpm | SHA-256: a24b907eb1bd41a5ac483259315e7c4baaced6d4177e9bfe718ba0a88efa11d9 | | ppc64le | | | mod_http2-1.15.19-4.el9_2.8.ppc64le.rpm | SHA-256: 996f183bb290415a33574fffefee193069f26378694cb1c1d9d28ce71e873a96 | | mod_http2-debuginfo-1.15.19-4.el9_2.8.ppc64le.rpm | SHA-256: c428e7bb27a0a4e87dd95910aca9d4a085213cbf9c1067f162c926f98ccb00fd | | mod_http2-debugsource-1.15.19-4.el9_2.8.ppc64le.rpm | SHA-256: 2a3370487f6c40c8e716797e4bf05e74fa30ccfbe1cee16dfe74d76d77d5af97 | Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 9.2 | SRPM | | |---|---| | mod_http2-1.15.19-4.el9_2.8.src.rpm | SHA-256: a24b907eb1bd41a5ac483259315e7c4baaced6d4177e9bfe718ba0a88efa11d9 | | s390x | | | mod_http2-1.15.19-4.el9_2.8.s390x.rpm | SHA-256: db2efc4f6acbfe234a5859188aec93c9a1bedf9911fa86e6c5880e31aa6a6e5c | | mod_http2-debuginfo-1.15.19-4.el9_2.8.s390x.rpm | SHA-256: 8f9148749feab3879d916df984d98233fef19e201406acaa57d804e7bd2456da | | mod_http2-debugsource-1.15.19-4.el9_2.8.s390x.rpm | SHA-256: 836f975a6688fec7f3e18087104cea601790b426054341779c6b37d8bf4c6bc7 | The Red Hat security contact is secalert@redhat.com. More contact details at https://access.redhat.com/security/team/contact/.