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.
History

Tue, 10 Nov 2026 12:45:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

threat_severity

Moderate


Tue, 10 Nov 2026 08:45:00 +0000

Type Values Removed Values Added
First Time appeared Fluxbox-team
Fluxbox-team fluxbox
Vendors & Products Fluxbox-team
Fluxbox-team fluxbox

Sat, 07 Nov 2026 07:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 06 Nov 2026 15:15:00 +0000

Type Values Removed Values Added
Description 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.
Title Fluxbox through 1.3.7 Infinite Loop via Menu::updateMenu() Style Geometry
Weaknesses CWE-835
References
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 6.8, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-11-06T15:01:01.397Z

Updated: 2026-11-06T16:46:17.952Z

Reserved: 2026-11-06T14:37:46.448Z

Link: CVE-2026-123785

cve-icon Vulnrichment

Updated: 2026-11-06T16:46:00.951Z

cve-icon NVD

Status : Received

Published: 2026-11-06T15:17:21.467

Modified: 2026-11-06T17:17:21.097

Link: CVE-2026-123785

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-11-06T15:01:01Z

Links: CVE-2026-123785 - Bugzilla