Red Hat Product Errata RHSA-2026:99754 - Security Advisory
Issued:
2026-11-12
Updated:
2026-11-12

RHSA-2026:99754 - Security Advisory

Synopsis

Important: libX11 security update

Type/Severity

Security Advisory: Important

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Identify and remediate systems affected by this advisory.

View affected systems

Topic

An update for libX11 is now available for Red Hat Enterprise Linux 7 Extended Lifecycle Support.

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 libX11 packages contain the core X11 protocol client library.

Security Fix(es):

  • libX11: libX11: Heap-based buffer overflow via malicious X server (CVE-2026-88806)

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 Server - Extended Life Cycle Support 7 x86_64
  • Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7 s390x
  • Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7 ppc64
  • Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7 ppc64le

Fixes

  • BZ - 2538514 - CVE-2026-88806 libX11: libX11: Heap-based buffer overflow via malicious X server

Red Hat Enterprise Linux Server - Extended Life Cycle Support 7

SRPM
libX11-1.6.7-5.el7_9.1.src.rpm SHA-256: df90d4c1b7758bfd603e26eac2d3e91164eabc7cf89e3d5d22e6ecc166907de3
x86_64
libX11-1.6.7-5.el7_9.1.i686.rpm SHA-256: 0711638a0f4194d9e9f62f57b9c12aef3353701ad89489ba7b51efa093f4e72d
libX11-1.6.7-5.el7_9.1.x86_64.rpm SHA-256: 51fef52b4ee0ebd25b3821fe8698161fd20641e27d2351e6267a154f0913a9cd
libX11-common-1.6.7-5.el7_9.1.noarch.rpm SHA-256: 428eda4d852f5a7100c0f2d1258585fc54747787c8a338a65e6768a820607e77
libX11-debuginfo-1.6.7-5.el7_9.1.i686.rpm SHA-256: a5bd070a4a830d3271b4bb7b3ed0f6e921dabc3a7b083a1ffb51745e2c05d7ac
libX11-debuginfo-1.6.7-5.el7_9.1.x86_64.rpm SHA-256: 4f01df2a164c0ddbb84a7421e37ce995c558a9cd47e8212308bfed51e3da0b52
libX11-devel-1.6.7-5.el7_9.1.i686.rpm SHA-256: 3d99dd03abcacbfa52901f86138f30bd0f65d8d402a71e54921313e6368d4207
libX11-devel-1.6.7-5.el7_9.1.x86_64.rpm SHA-256: e89c64c3090b6034a26c640cdbb4f955b46ffe84808bfc79a2912caacb599f0c

Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7

SRPM
libX11-1.6.7-5.el7_9.1.src.rpm SHA-256: df90d4c1b7758bfd603e26eac2d3e91164eabc7cf89e3d5d22e6ecc166907de3
s390x
libX11-1.6.7-5.el7_9.1.s390.rpm SHA-256: 70b2a85f996c632f306cd52b77959e91f41944af8f5f4ed2e7ecf236c70d59fc
libX11-1.6.7-5.el7_9.1.s390x.rpm SHA-256: d4935f31fdde190b95188268888fbd5bfb75f51844535c4841174c6d0833ffa4
libX11-common-1.6.7-5.el7_9.1.noarch.rpm SHA-256: 428eda4d852f5a7100c0f2d1258585fc54747787c8a338a65e6768a820607e77
libX11-debuginfo-1.6.7-5.el7_9.1.s390.rpm SHA-256: 70a6b4aedef61baebf35e6de9fafa5944b4d937860a127f18d564aa13fbc1bd0
libX11-debuginfo-1.6.7-5.el7_9.1.s390x.rpm SHA-256: bc34626e33d4b0cebf3186246d8d03c10c770c06f3427eb683931140ff31659b
libX11-devel-1.6.7-5.el7_9.1.s390.rpm SHA-256: 040ec19b3158c4c9daf3a5469e8a71e32a2661a73d2587c738c2869cb94392fd
libX11-devel-1.6.7-5.el7_9.1.s390x.rpm SHA-256: 0939e6ac3d1330c64ac07887d2836486fcf2409862fadb44ba5bb89bab40486b

Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7

SRPM
libX11-1.6.7-5.el7_9.1.src.rpm SHA-256: df90d4c1b7758bfd603e26eac2d3e91164eabc7cf89e3d5d22e6ecc166907de3
ppc64
libX11-1.6.7-5.el7_9.1.ppc.rpm SHA-256: f74355f49a823bf25549f393ffc0958b31992f9d982781c11e2dc6a3d5e4237e
libX11-1.6.7-5.el7_9.1.ppc64.rpm SHA-256: 63aeacb1abb9d5a26bb38827e5d04f665b145114a7c9d36bc7c7e7b7d1f47f81
libX11-common-1.6.7-5.el7_9.1.noarch.rpm SHA-256: 428eda4d852f5a7100c0f2d1258585fc54747787c8a338a65e6768a820607e77
libX11-debuginfo-1.6.7-5.el7_9.1.ppc.rpm SHA-256: fa372928483ad8a3f00d2f80ce2471edcb8676b3b3452ce0426f9ca4a216fe0f
libX11-debuginfo-1.6.7-5.el7_9.1.ppc64.rpm SHA-256: 1fd9146f25f0a0a903619450f36eab4c799edb486aa79d17c374cf3fb9a6f5f1
libX11-devel-1.6.7-5.el7_9.1.ppc.rpm SHA-256: 4429dd15f6600a7c6e61af03ba1c4c366940afa96c11d774ba6ae99e42a21830
libX11-devel-1.6.7-5.el7_9.1.ppc64.rpm SHA-256: 86fcbe425f69c7f7a5ce18ec46d0e9fe6aeefb065e00ed4c9b15a2e4af0aa21a

Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7

SRPM
libX11-1.6.7-5.el7_9.1.src.rpm SHA-256: df90d4c1b7758bfd603e26eac2d3e91164eabc7cf89e3d5d22e6ecc166907de3
ppc64le
libX11-1.6.7-5.el7_9.1.ppc64le.rpm SHA-256: 6f28396736bdf7d6e34e96f77902b4a6a4c21deae9a1e6f835d7fb311a228983
libX11-common-1.6.7-5.el7_9.1.noarch.rpm SHA-256: 428eda4d852f5a7100c0f2d1258585fc54747787c8a338a65e6768a820607e77
libX11-debuginfo-1.6.7-5.el7_9.1.ppc64le.rpm SHA-256: 2b1d44a30497a73ba51e9724cffc6a7687a859f056b35d9bcbd0cfef6a75fac3
libX11-devel-1.6.7-5.el7_9.1.ppc64le.rpm SHA-256: a82fba0289bc4417f6ccfb25d761f1e5e5968bc45bc5b544c5bb83375a8967bc

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