Bug 2568289 (CVE-2026-123785)

Summary: CVE-2026-123785 fluxbox: fluxbox: Denial of Service via crafted style geometry values
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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OS: Linux   
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A flaw was found in Fluxbox. This vulnerability allows an attacker to cause an infinite loop by providing a crafted style configuration containing oversized geometry values, such as an unbounded menu title height. When the style is loaded, the window manager hangs, resulting in sustained CPU utilization and a Denial of Service (DoS).
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Description OSIDB Bzimport 2026-11-06 15:12:34 UTC 
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.