What’s Vulnerable › Vulnerabilities

CVE-2025-49177: Xorg-x11-server-xwayland: xorg-x11-server: tigervnc: data leak in xfixes extension's xfixessetclientdisconnectmode

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-06-17 · updated 2026-06-30
• Weakness: CWE-200

Description

A flaw was found in the XFIXES extension. The XFixesSetClientDisconnectMode handler does not validate the request length, allowing a client to read unintended memory from previous requests.

Affected products

• Red Hat Enterprise Linux 10: all versions — fixed in 0:24.1.5-4.el10_0
• Red Hat Enterprise Linux 6: all versions
• Red Hat Enterprise Linux 7: all versions
• Red Hat Enterprise Linux 8: all versions
• Red Hat Enterprise Linux 9: all versions — fixed in 0:1.20.11-31.el9_6, 0:23.2.7-4.el9_6
• Red Hat Enterprise Linux 9.4 Extended Update Support: all versions — fixed in 0:22.1.9-6.el9_4
• X.Org xwayland: before 24.1.7 — fixed in 24.1.7

How to fix

Upgrade to a fixed version: Red Hat Enterprise Linux 10 0:24.1.5-4.el10_0; Red Hat Enterprise Linux 9 0:1.20.11-31.el9_6, 0:23.2.7-4.el9_6; Red Hat Enterprise Linux 9.4 Extended Update Support 0:22.1.9-6.el9_4; X.Org xwayland 24.1.7. Check the vendor advisory for mitigations.

References

• https://access.redhat.com/errata/RHSA-2025:10258
• https://access.redhat.com/errata/RHSA-2025:9303
• https://access.redhat.com/errata/RHSA-2025:9304
• https://access.redhat.com/security/cve/CVE-2025-49177
• https://bugzilla.redhat.com/show_bug.cgi?id=2369955
• https://gitlab.freedesktop.org/xorg/xserver/-/commit/ab02fb96b1c701c3bb47617d965522c34befa6af
• https://www.x.org/wiki/Development/Security/

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