MyBB: Security Question insufficient validation
### Impact The registration component does not validate the text-based _Security Question_ CAPTCHA correctly, allowing attackers to bypass the challenge via a specially crafted value. [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N](https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)…
Severity medium: primary CNA CVSS 5.3 v3.1 (worst CNA-provided scenario) Not listed in this KEV snapshot. Forecast present in this snapshot.
Published 2026-08-18T15:44:59.644Z. Updated 2026-08-18T17:46:31.511Z.