Is there a public exploit for CVE-2026-121604?

No public exploit for CVE-2026-121604 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-121604?

CVE-2026-121604 scores CVSS 4.8 (v4.0), rated medium.

What does CVE-2026-121604 affect?

CVE-2026-121604 affects wlroots wlroots.

4.8 Medium

wlroots before 0.20.2 contains an out-of-bounds read vulnerability in readsurfaceclass() in xwayland/xwm.c that allows local X11 clients to…

CVE-2026-121604

wlroots before 0.20.2 contains an out-of-bounds read vulnerability in readsurfaceclass() in xwayland/xwm.c that allows local X11 clients to leak compositor heap memory. Attackers can set a WMCLASS property with a NUL-terminated instance but unterminated class, exposing over-read heap bytes as the window class or appid over IPC.

Assessment

CVSS: 4.8 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 3 November 2026
Last updated: 3 November 2026
Affected: wlroots · wlroots
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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