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.

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.