AIL did not restrict repeated failed attempts to verify a two-factor authentication (OTP) code. An attacker who had reached the 2FA verification step, such as after successfully completing the password-authentication stage, could submit an unlimited number of OTP guesses. This could enable brute-force guessing of a valid code and bypass the intended second authentication factor, resulting in unauthorized account access.
The patch introduces per-user failed-OTP tracking, blocks verification after 30 failed attempts for one hour, clears the counter after a successful OTP verification, and provides administrator recovery actions to purge affected lockouts.
Exploitability
AV:NAC:LAT:NPR:NUI:AVulnerable System
VC:LVI:NVA:NSubsequent System
SC:NSI:NSA:N5.1/CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:NOther