Bug 2568284 (CVE-2026-123784)

Summary: CVE-2026-123784 fluxbox: fluxbox: Arbitrary command execution via crafted style background values
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Fluxbox. This vulnerability allows an attacker to execute arbitrary commands by convincing a user to load a specially crafted style file. When processing the style, unescaped background configuration values are passed directly to a system shell command, leading to command execution with the privileges of the victim.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-11-06 15:12:22 UTC
Fluxbox through 1.3.7 contains an OS command injection vulnerability in RootTheme::reconfigTheme() that allows attackers to execute commands via crafted style background values. Attackers can embed shell metacharacters in background pixmap paths, random directories, or gradient texture text, which are concatenated unescaped into an fbsetbg command run via $SHELL -c when the style loads.