RHSA-2026:34355 - Security Advisory

Topic

An update for mod_http2 is now available for Red Hat Enterprise Linux 10.

Red Hat Product Security has rated this update as having a security impact of Moderate. 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):

• httpd: mod_http2: Apache HTTP Server mod_http2: Use After Free vulnerability allows arbitrary code execution or denial of service. (CVE-2026-48913)
• httpd: Apache HTTP Server: Out-of-bounds Read in mod_headers and mod_mime (CVE-2026-43951)

Bug Fix(es) and Enhancement(s):

• address CVE-2026-43951 and CVE-2026-48913 in mod_http2 (JIRA:RHEL-188008)

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:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 10 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.2 x86_64
• Red Hat Enterprise Linux for IBM z Systems 10 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.2 s390x
• Red Hat Enterprise Linux for Power, little endian 10 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.2 ppc64le
• Red Hat Enterprise Linux for ARM 64 10 aarch64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.2 aarch64
• Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.2 aarch64
• Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.2 s390x
• Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.2 ppc64le
• Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.2 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 10.2 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 10.2 aarch64
• Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 10.2 ppc64le
• Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 10.2 s390x

Fixes

• BZ - 2486405 - CVE-2026-48913 httpd: mod_http2: Apache HTTP Server mod_http2: Use After Free vulnerability allows arbitrary code execution or denial of service.
• BZ - 2486415 - CVE-2026-43951 httpd: Apache HTTP Server: Out-of-bounds Read in mod_headers and mod_mime

CVEs

• CVE-2026-43951
• CVE-2026-48913

References

• https://access.redhat.com/security/updates/classification/#moderate