CVE-2026-123785 Fluxbox through 1.3.7 Infinite Loop via Menu::updateMenu() Style Geometry
MediumCVSS 6.8
EPSS 0.17%
- Published
- Updated
- Exploit status
- No public exploit known
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.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| debian/fluxbox(Debian:12) | All versions | No fix listed |
| debian/fluxbox(Debian:14) | All versions | No fix listed |
| debian/fluxbox(Debian:13) | All versions | No fix listed |
| fluxbox/fluxbox | <= 1.3.7 | No fix listed |
| ubuntu/fluxbox(Ubuntu:22.04) | All versions | No fix listed |
| ubuntu/fluxbox(Ubuntu:24.04) | All versions | No fix listed |
| ubuntu/fluxbox(Ubuntu:26.04) | All versions | No fix listed |
| ubuntu/fluxbox(Ubuntu:26.10) | All versions | No fix listed |
| debian/fluxbox(Debian:12) | = 1.3.5-2.1 | No fix listed |
| debian/fluxbox(Debian:12) | = 1.3.6-1~exp1 | No fix listed |
| debian/fluxbox(Debian:12) | = 1.3.7-1 | No fix listed |
| debian/fluxbox(Debian:12) | = 1.3.7-1~exp1 | No fix listed |
| debian/fluxbox(Debian:13) | = 1.3.7-1 | No fix listed |
| debian/fluxbox(Debian:14) | = 1.3.7-1 | No fix listed |
References
- Red Hat CVE page mitigation vendor-advisory
- Red Hat Bugzilla 2568289 issue-tracking
- www.cve.org
- nvd.nist.gov
- github.com product
- Menu::updateMenu column loop technical-description
- Pull Request #90 issue-tracking patch
- VulnCheck Advisory: Fluxbox through 1.3.7 Infinite Loop via Menu::updateMenu() Style Geometry third-party-advisory
- Debian Security Tracker CVE-2026-123785 vendor-advisory
- bugs.debian.org issue-tracking
- Ubuntu CVE tracker vendor-advisory