Psono Server versions 5.3.5 through 7.2.3 used a permission class that did not enforce token write scope when claiming a device code. An authenticated remote attacker holding a restricted API key-derived session could claim an attacker-controlled device code and obtain a full read-write session valid for up to 365 days, bypassing the original token's scope and lifetime restrictions. This did not bypass two-factor authentication or directly disclose plaintext secrets.