Remote login tokens are generated from only 4 bytes of randomness (32 bits = ~4
billion possibilities, 8 hex characters). The /ajax/verify_token endpoint at
remotelogin.py:98 has no rate limiting. The token is valid for 10 minutes.
At even modest request rates (10,000 req/sec), an attacker can test ~6 million
tokens during the 10-minute window , which isn't enough to exhaust the full
space, sure, but combined with multiple concurrent login sessions (each
generating a new token), or if the attacker can trigger the victim to initiate
remote login, the attack becomes more feasible. Compare with the Kobo auth
token which uses urandom(16) (128 bits).
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