CVE-2026-121604
wlroots before 0.20.2 Out-of-Bounds Read via read_surface_class() in xwm.c
CVSS Score
3.3
EPSS Score
0.0%
EPSS Percentile
0th
wlroots before 0.20.2 contains an out-of-bounds read vulnerability in read_surface_class() in xwayland/xwm.c that allows local X11 clients to leak compositor heap memory. Attackers can set a WM_CLASS property with a NUL-terminated instance but unterminated class, exposing over-read heap bytes as the window class or app_id over IPC.
| CWE | CWE-125 |
| Vendor | wlroots |
| Product | wlroots |
| Published | Nov 3, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None
Affected Versions
wlroots / wlroots
0 < 0.20.2
References
gitlab.freedesktop.org: https://gitlab.freedesktop.org/wlroots/wlroots/-/work_items/4092 gitlab.freedesktop.org: https://gitlab.freedesktop.org/wlroots/wlroots/-/merge_requests/5374 gitlab.freedesktop.org: https://gitlab.freedesktop.org/wlroots/wlroots/-/commit/851cdd0089004884bd85a95ad21f04009cb5a53a gitlab.freedesktop.org: https://gitlab.freedesktop.org/wlroots/wlroots/-/commit/4412992469540b1d578cb94a5cd4e6e5829812dc gitlab.freedesktop.org: https://gitlab.freedesktop.org/wlroots/wlroots/-/releases/0.20.2 gitlab.freedesktop.org: https://gitlab.freedesktop.org/wlroots/wlroots/-/blob/0.20.1/xwayland/xwm.c#L661-L678 vulncheck.com: https://www.vulncheck.com/advisories/wlroots-before-0.20.2-out-of-bounds-read-via-read-surface-class-in-xwm-c
Credits
Tristan Madani (Talence Security) Simon Ser