CVE-2026-40935
Medium · 5.3CVSS
5.3
EPSS
0.3%
Published
Apr 21, 2026
CISA due date
—
The record
WWBN AVideo is an open source video platform. In versions 29.0 and prior, `objects/getCaptcha.php` accepts the CAPTCHA length (`ql`) directly from the query string with no clamping or sanitization, letting any unauthenticated client force the server to generate a 1-character CAPTCHA word. Combined with a case-insensitive `strcasecmp` comparison over a ~33-character alphabet and the fact that failed validations do NOT consume the stored session token, an attacker can trivially brute-force the CAPTCHA on any endpoint that relies on `Captcha::validation()` (user registration, password recovery, contact form, etc.) in at most ~33 requests per session. Commit bf1c76989e6a9054be4f0eb009d68f0f2464b453 contains a fix.
Affected packages
| Ecosystem | Package | Introduced | Fixed |
|---|
Related vulnerabilities
- GHSA-hg7g-56h5-5pqr CAPTCHA Bypass in WWBN/AVideo via Attacker-Controlled Length Parameter and Missing Token… Same vulnerability
- CVE-2026-49953 Discuz! CWE-804
- CVE-2025-70129 If the anti spam-captcha functionality in PluXml versions 5.8.22 and earlier is enabled… CWE-804
- CVE-2026-27411 Guessable CAPTCHA vulnerability in jp-secure SiteGuard WP Plugin siteguard allows… CWE-804