{"id":"CVE-2026-40935","summary":"WWBN/AVideo has CAPTCHA Bypass via Attacker-Controlled Length Parameter and Missing Token Invalidation on Failure","details":"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.","aliases":["GHSA-hg7g-56h5-5pqr"],"modified":"2026-08-12T03:51:28.856708196Z","published":"2026-04-21T22:21:17.009Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-804"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40935.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40935.json"},{"type":"ADVISORY","url":"https://github.com/WWBN/AVideo/security/advisories/GHSA-hg7g-56h5-5pqr"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-40935"},{"type":"FIX","url":"https://github.com/WWBN/AVideo/commit/bf1c76989e6a9054be4f0eb009d68f0f2464b453"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/wwbn/avideo","events":[{"introduced":"0"},{"fixed":"bf1c76989e6a9054be4f0eb009d68f0f2464b453"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"last_affected":"29.0"}],"source":["CPE_RANGE","REFERENCES"],"cpe":"cpe:2.3:a:wwbn:avideo:*:*:*:*:*:*:*:*"}}],"versions":["29.0","26.0","25.0","24.0","22.0","21.0","18.0","14.3.1","14.3","12.4","11.6","11.5","11.1.1","11.1","11","10.8","8.9.1","8.9","8.7","8.6","8.5","8.1","7.8","7.7","7.6","7.4","7.3","7.2","4.0","3.4","2.7","2.2"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40935.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N"}]}