DoLogin Security <= 4.3 - Unauthenticated Authentication Bypass via Insufficient Randomness via 'dologin' Parameter Weak PRNG Token

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.

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: DoLogin Security 4.4 closes this, and updating the plugin is the step that ends it.

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