Skip to navigation Skip to main content

Utilities

  • Subscriptions
  • Downloads
  • Red Hat Console
  • Get Support
Red Hat Customer Portal
  • Subscriptions
  • Downloads
  • Red Hat Console
  • Get Support
  • Products

    Top Products

    • Red Hat Enterprise Linux
    • Red Hat OpenShift
    • Red Hat Ansible Automation Platform
    All Products

    Downloads and Containers

    • Downloads
    • Packages
    • Containers

    Top Resources

    • Documentation
    • Product Life Cycles
    • Product Compliance
    • Errata
  • Knowledge

    Red Hat Knowledge Center

    • Knowledgebase Solutions
    • Knowledgebase Articles
    • Customer Portal Labs
    • Errata

    Top Product Docs

    • Red Hat Enterprise Linux
    • Red Hat OpenShift
    • Red Hat Ansible Automation Platform
    All Product Docs

    Training and Certification

    • About
    • Course Index
    • Certification Index
    • Skill Assessment
  • Security

    Red Hat Product Security Center

    • Security Updates
    • Security Advisories
    • Red Hat CVE Database
    • Errata

    References

    • Security Bulletins
    • Severity Ratings
    • Security Data

    Top Resources

    • Security Labs
    • Backporting Policies
    • Security Blog
  • Support

    Red Hat Support

    • Support Cases
    • Troubleshoot
    • Get Support
    • Contact Red Hat Support

    Red Hat Community Support

    • Customer Portal Community
    • Community Discussions
    • Red Hat Accelerator Program

    Top Resources

    • Product Life Cycles
    • Customer Portal Labs
    • Red Hat JBoss Supported Configurations
    • Red Hat Lightspeed
Or troubleshoot an issue.

Select Your Language

  • English
  • Français
  • 한국어
  • 日本語
  • 中文 (中国)

Infrastructure and Management

  • Red Hat Enterprise Linux
  • Red Hat Satellite
  • Red Hat Subscription Management
  • Red Hat Lightspeed
  • Red Hat Ansible Automation Platform

Cloud Computing

  • Red Hat OpenShift
  • Red Hat OpenStack Platform
  • Red Hat OpenShift
  • Red Hat OpenShift AI
  • Red Hat OpenShift Dedicated
  • Red Hat Advanced Cluster Security for Kubernetes
  • Red Hat Advanced Cluster Management for Kubernetes
  • Red Hat Quay
  • Red Hat OpenShift Dev Spaces
  • Red Hat OpenShift Service on AWS

Storage

  • Red Hat Gluster Storage
  • Red Hat Hyperconverged Infrastructure
  • Red Hat Ceph Storage
  • Red Hat OpenShift Data Foundation

Runtimes

  • Red Hat Runtimes
  • Red Hat JBoss Enterprise Application Platform
  • Red Hat Data Grid
  • Red Hat JBoss Web Server
  • Red Hat build of Keycloak
  • Red Hat support for Spring Boot
  • Red Hat build of Node.js
  • Red Hat build of Quarkus

Integration and Automation

  • Red Hat Application Foundations
  • Red Hat Fuse
  • Red Hat AMQ
  • Red Hat 3scale API Management
All Products
Red Hat Product Errata RHSA-2026:95499 - Security Advisory
Issued:
2026-11-05
Updated:
2026-11-05

RHSA-2026:95499 - Security Advisory

  • Overview
  • Updated Packages

Synopsis

Important: libX11 security update

Type/Severity

Security Advisory: Important

Red Hat Lightspeed patch analysis

Identify and remediate systems affected by this advisory.

View affected systems

Topic

An update for libX11 is now available for Red Hat Enterprise Linux 10.0 Extended Update 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 for x86_64 - Extended Update Support 10.0 x86_64
  • Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.0 s390x
  • Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.0 ppc64le
  • Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.0 aarch64
  • Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.0 aarch64
  • Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.0 s390x
  • Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.0 ppc64le
  • Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.0 x86_64

Fixes

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

CVEs

  • CVE-2026-88806

References

  • https://access.redhat.com/security/updates/classification/#important
Note: More recent versions of these packages may be available. Click a package name for more details.

Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.0

SRPM
libX11-1.8.10-1.el10_0.1.src.rpm SHA-256: c69f41edac93c8353d54c7c335e4089143746d870dd140e47022d7ed4cc54e15
x86_64
libX11-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: 7e51b948929c5d2907d1f350465cec7b632051cc2245191fc3ace08a3bc49b72
libX11-common-1.8.10-1.el10_0.1.noarch.rpm SHA-256: 25cc66cb26bf75b1f63ce53e0561a773b1556f2f0fe4279d25b542beed145b82
libX11-debuginfo-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: b0d7ae67f92f3a71119ca3fc5c6484c7cd8956712b1a520dddca7d4ddbcba720
libX11-debugsource-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: d3e4c5ae7044b486a00d4af4a83033256269e64fc64069953ac8e6358c3919ae
libX11-devel-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: 487e8e08ff46022065cbf5f7d88904ca6c9f0595b48bbe209a69ea3fea29ec78
libX11-xcb-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: 37144415acab1d8af36c77cf0c2caf4dd203c429ad0ff658dca5f09c4aecb689
libX11-xcb-debuginfo-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: f43271a5f7d8f500d759248372cf079de73855c0f812410208efbb37d1a55218

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.0

SRPM
libX11-1.8.10-1.el10_0.1.src.rpm SHA-256: c69f41edac93c8353d54c7c335e4089143746d870dd140e47022d7ed4cc54e15
s390x
libX11-1.8.10-1.el10_0.1.s390x.rpm SHA-256: caa4e0f26159bace9de7f999a9a3cb42bb82124df335adb37316ecd6361656ce
libX11-common-1.8.10-1.el10_0.1.noarch.rpm SHA-256: 25cc66cb26bf75b1f63ce53e0561a773b1556f2f0fe4279d25b542beed145b82
libX11-debuginfo-1.8.10-1.el10_0.1.s390x.rpm SHA-256: 0c5bae88966a0c02940b4036a2c3ef919fc1e6e8261ea141ec97ad8d2609e411
libX11-debugsource-1.8.10-1.el10_0.1.s390x.rpm SHA-256: 695d4f091e1d8318593953f215e0e4581725c38e2f9d2edfa19dfb65a8362934
libX11-devel-1.8.10-1.el10_0.1.s390x.rpm SHA-256: ffa10a564dbfcf6a4123a602f0c1de72827f11155d525e15ed34c8d4a2ffffcc
libX11-xcb-1.8.10-1.el10_0.1.s390x.rpm SHA-256: 47ffe66184ed7d52b06b3fa8e4675fc2d4dc44610c807ea8ce0b08ee04fdb4ce
libX11-xcb-debuginfo-1.8.10-1.el10_0.1.s390x.rpm SHA-256: d1e464c7156472fa7cad7046203ffcdf26856d62fa3d3333e1ce756b6eb71483

Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.0

SRPM
libX11-1.8.10-1.el10_0.1.src.rpm SHA-256: c69f41edac93c8353d54c7c335e4089143746d870dd140e47022d7ed4cc54e15
ppc64le
libX11-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: 85951b51a1ff91ee0b8566fb80b9b3ce5c17d8fe76b97cbf0d92be6795e61520
libX11-common-1.8.10-1.el10_0.1.noarch.rpm SHA-256: 25cc66cb26bf75b1f63ce53e0561a773b1556f2f0fe4279d25b542beed145b82
libX11-debuginfo-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: 79679a9fb96efc5f43ab129ce7a3f225cd10fe2a63cd211974034956c12cc42d
libX11-debugsource-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: 269642f9512d833cc598e8f1432e2e9fb77391af26fec9248784a7c6759e7742
libX11-devel-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: a6a522d921a29545e42476eb1bd144279a56828b744717d0bcd63e923db5805f
libX11-xcb-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: 0c67d78ed53759237cbc7755cd9e58c7a8ae7dc6ec153c092f188432c57b7f11
libX11-xcb-debuginfo-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: bc6919b1b3792895dc106315180b9a8685818fd3079f321409569447b55e7ebb

Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.0

SRPM
libX11-1.8.10-1.el10_0.1.src.rpm SHA-256: c69f41edac93c8353d54c7c335e4089143746d870dd140e47022d7ed4cc54e15
aarch64
libX11-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: 80931be8b805b9fb67c36381d1c1feee3a7d341f4e5b8753ebfd66ebdb162161
libX11-common-1.8.10-1.el10_0.1.noarch.rpm SHA-256: 25cc66cb26bf75b1f63ce53e0561a773b1556f2f0fe4279d25b542beed145b82
libX11-debuginfo-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: 7068e3a1e36c79cd730b0c645bded5f3b7e0d69cb423924ac3315bbddbb83f88
libX11-debugsource-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: 10ae8aab79e4b866b2e3d2757c38c718041ed6cd4a43a766dfe886bf24ee0b7c
libX11-devel-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: d47ee166d8e7f8b488f9fecd8ecfb12b31024cbfddca8981952e2b19e6b98510
libX11-xcb-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: afc6e8cb8f57fce4116da3f2638669a1bd05035b8f09b8be303033f58eec66eb
libX11-xcb-debuginfo-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: 8ff9079cef6237faec9f1e5453dcd0697cedeec54ade397be56f76ce8507d87a

Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.0

SRPM
libX11-1.8.10-1.el10_0.1.src.rpm SHA-256: c69f41edac93c8353d54c7c335e4089143746d870dd140e47022d7ed4cc54e15
aarch64
libX11-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: 80931be8b805b9fb67c36381d1c1feee3a7d341f4e5b8753ebfd66ebdb162161
libX11-common-1.8.10-1.el10_0.1.noarch.rpm SHA-256: 25cc66cb26bf75b1f63ce53e0561a773b1556f2f0fe4279d25b542beed145b82
libX11-debuginfo-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: 7068e3a1e36c79cd730b0c645bded5f3b7e0d69cb423924ac3315bbddbb83f88
libX11-debugsource-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: 10ae8aab79e4b866b2e3d2757c38c718041ed6cd4a43a766dfe886bf24ee0b7c
libX11-devel-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: d47ee166d8e7f8b488f9fecd8ecfb12b31024cbfddca8981952e2b19e6b98510
libX11-xcb-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: afc6e8cb8f57fce4116da3f2638669a1bd05035b8f09b8be303033f58eec66eb
libX11-xcb-debuginfo-1.8.10-1.el10_0.1.aarch64.rpm SHA-256: 8ff9079cef6237faec9f1e5453dcd0697cedeec54ade397be56f76ce8507d87a

Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.0

SRPM
libX11-1.8.10-1.el10_0.1.src.rpm SHA-256: c69f41edac93c8353d54c7c335e4089143746d870dd140e47022d7ed4cc54e15
s390x
libX11-1.8.10-1.el10_0.1.s390x.rpm SHA-256: caa4e0f26159bace9de7f999a9a3cb42bb82124df335adb37316ecd6361656ce
libX11-common-1.8.10-1.el10_0.1.noarch.rpm SHA-256: 25cc66cb26bf75b1f63ce53e0561a773b1556f2f0fe4279d25b542beed145b82
libX11-debuginfo-1.8.10-1.el10_0.1.s390x.rpm SHA-256: 0c5bae88966a0c02940b4036a2c3ef919fc1e6e8261ea141ec97ad8d2609e411
libX11-debugsource-1.8.10-1.el10_0.1.s390x.rpm SHA-256: 695d4f091e1d8318593953f215e0e4581725c38e2f9d2edfa19dfb65a8362934
libX11-devel-1.8.10-1.el10_0.1.s390x.rpm SHA-256: ffa10a564dbfcf6a4123a602f0c1de72827f11155d525e15ed34c8d4a2ffffcc
libX11-xcb-1.8.10-1.el10_0.1.s390x.rpm SHA-256: 47ffe66184ed7d52b06b3fa8e4675fc2d4dc44610c807ea8ce0b08ee04fdb4ce
libX11-xcb-debuginfo-1.8.10-1.el10_0.1.s390x.rpm SHA-256: d1e464c7156472fa7cad7046203ffcdf26856d62fa3d3333e1ce756b6eb71483

Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.0

SRPM
libX11-1.8.10-1.el10_0.1.src.rpm SHA-256: c69f41edac93c8353d54c7c335e4089143746d870dd140e47022d7ed4cc54e15
ppc64le
libX11-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: 85951b51a1ff91ee0b8566fb80b9b3ce5c17d8fe76b97cbf0d92be6795e61520
libX11-common-1.8.10-1.el10_0.1.noarch.rpm SHA-256: 25cc66cb26bf75b1f63ce53e0561a773b1556f2f0fe4279d25b542beed145b82
libX11-debuginfo-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: 79679a9fb96efc5f43ab129ce7a3f225cd10fe2a63cd211974034956c12cc42d
libX11-debugsource-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: 269642f9512d833cc598e8f1432e2e9fb77391af26fec9248784a7c6759e7742
libX11-devel-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: a6a522d921a29545e42476eb1bd144279a56828b744717d0bcd63e923db5805f
libX11-xcb-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: 0c67d78ed53759237cbc7755cd9e58c7a8ae7dc6ec153c092f188432c57b7f11
libX11-xcb-debuginfo-1.8.10-1.el10_0.1.ppc64le.rpm SHA-256: bc6919b1b3792895dc106315180b9a8685818fd3079f321409569447b55e7ebb

Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.0

SRPM
libX11-1.8.10-1.el10_0.1.src.rpm SHA-256: c69f41edac93c8353d54c7c335e4089143746d870dd140e47022d7ed4cc54e15
x86_64
libX11-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: 7e51b948929c5d2907d1f350465cec7b632051cc2245191fc3ace08a3bc49b72
libX11-common-1.8.10-1.el10_0.1.noarch.rpm SHA-256: 25cc66cb26bf75b1f63ce53e0561a773b1556f2f0fe4279d25b542beed145b82
libX11-debuginfo-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: b0d7ae67f92f3a71119ca3fc5c6484c7cd8956712b1a520dddca7d4ddbcba720
libX11-debugsource-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: d3e4c5ae7044b486a00d4af4a83033256269e64fc64069953ac8e6358c3919ae
libX11-devel-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: 487e8e08ff46022065cbf5f7d88904ca6c9f0595b48bbe209a69ea3fea29ec78
libX11-xcb-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: 37144415acab1d8af36c77cf0c2caf4dd203c429ad0ff658dca5f09c4aecb689
libX11-xcb-debuginfo-1.8.10-1.el10_0.1.x86_64.rpm SHA-256: f43271a5f7d8f500d759248372cf079de73855c0f812410208efbb37d1a55218

The Red Hat security contact is secalert@redhat.com. More contact details at https://access.redhat.com/security/team/contact/.

Red Hat LinkedIn YouTube Facebook X, formerly Twitter

Quick Links

  • Downloads
  • Subscriptions
  • Support Cases
  • Customer Service
  • Product Documentation

Help

  • Contact Us
  • Customer Portal FAQ
  • Log-in Assistance

Site Info

  • Trust Red Hat
  • Browser Support Policy
  • Accessibility
  • Awards and Recognition
  • Colophon

Related Sites

  • redhat.com
  • developers.redhat.com
  • connect.redhat.com
  • cloud.redhat.com

Red Hat legal and privacy links

  • About Red Hat
  • Jobs
  • Events
  • Locations
  • Contact Red Hat
  • Red Hat Blog
  • Inclusion at Red Hat
  • Cool Stuff Store
  • Red Hat Summit
© 2026 Red Hat

Red Hat legal and privacy links

  • Privacy statement
  • Terms of use
  • All policies and guidelines
  • Digital accessibility