CVE-2026-123785

CVSS 6.8 (medium) · published 2026-11-06

Fluxbox through 1.3.7 contains an infinite loop vulnerability in Menu::updateMenu() in src/FbTk/Menu.cc that allows attackers to hang the window manager via crafted style geometry values. Attackers can supply a style with an oversized unbounded menu.titleHeight so the column loop never terminates, causing sustained CPU use and denial of service at startup.

Weakness: CWE-835

Source: NVD CVE-2026-123785

References

• https://github.com/fluxbox/fluxbox
• https://github.com/fluxbox/fluxbox/blob/Release-1_3_7/src/FbTk/Menu.cc#L433-L448
• https://github.com/fluxbox/fluxbox/pull/90
• https://www.vulncheck.com/advisories/fluxbox-through-1.3.7-infinite-loop-via-menu-updatemenu-style-geometry

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