CVE-2025-26599: Red Hat Enterprise Linux

High severity, CVSS 7.8. EPSS: 0.4% chance of exploitation in the next 30 days.

An access to an uninitialized pointer flaw was found in X.Org and Xwayland. The function compCheckRedirect() may fail if it cannot allocate the backing pixmap. In that case, compRedirectWindow() will return a BadAlloc error without validating the window tree marked just before, which leaves the validated data partly initialized and the use of an uninitialized pointer later.

Affected products

• Red Hat Enterprise Linux: version 7.0 only; version 8.0 only; version 9.0 only
• Tigervnc Tigervnc: affected versions not specified
• X.org X Server: before 21.1.16 (fixed in 21.1.16)
• X.org Xwayland: before 24.1.6 (fixed in 24.1.6)

Published 2025-02-25. Last modified 2026-06-29.