The DoLogin Security plugin for WordPress is vulnerable to Authentication Bypass via Insufficient Randomness in all versions up to, and including, 4.3. The vulnerability exists because `dologin\s::rrand()` seeds the Mersenne Twister with `mt_srand((double) microtime() * 1000000)` — discarding the integer-seconds component of `microtime()` and constraining the seed to a range of approximately 10^6 values (~20 bits of entropy) — after which every character of the 32-character magic-link token is d
The DoLogin Security plugin for WordPress is vulnerable to Authentication Bypass via Insufficient Randomness in all versions up to, and including, 4.3. The vulnerability exists because dologin\s::rrand() seeds the Mersenne Twister with mt_srand((double) microtime() * 1000000) — discarding the integer-seconds component of microtime() and constraining the seed to a range of approximately 10^6 values (~20 bits of entropy) — after which every character of the 32-character magic-link token is drawn sequentially with mt_rand(), making the entire token a deterministic function of that seed. Because Pswdless::try_login() is registered on the unauthenticated init hook, resolves the target account by the auto-increment numeric ID embedded in the ?dologin=<id>.<hash> parameter, performs the hash comparison using a non-constant-time != operator, and then calls wp_set_auth_cookie() directly — never passing through wp_authenticate() and therefore never triggering the plugin's own Auth::_has_login_err() lockout — an unauthenticated attacker can brute-force the ~10^6-candidate seed space to reconstruct an active passwordless login token and authenticate as any targeted user, including administrators, without a password. Exploitation requires that a valid, unexpired passwordless login link (active for up to 7 days) exists for the target account at the time of the attack, and that the numeric link ID is known or guessable from the auto-increment primary key.
Why this VPI (explainable, experimental)
VPI breakdown
| Impact | 88.00 |
| Exploitation signal(No additional exploitation signal) | ×1.00 |
| VPI | 88.00 |
VPI formula vpi-v1