In Connect2id Nimbus JOSE+JWT before 9.37.2, an attacker can cause a denial of service (resource consumption) via a large JWE p2c header value (aka iteration count) for the PasswordBasedDecrypter (PBKDF2) component.

Connect2id Nimbus JOSE+JWT before v7.9 can throw various uncaught exceptions while parsing a JWT, which could result in an application crash (potential information disclosure) or a potential authentication bypass.

Nimbus JOSE+JWT before 4.36 proceeds with ECKey construction without ensuring that the public x and y coordinates are on the specified curve, which allows attackers to conduct an Invalid Curve Attack in environments where the JCE provider lacks the applicable curve validation.

Nimbus JOSE+JWT before 4.39 proceeds improperly after detection of an invalid HMAC in authenticated AES-CBC decryption, which allows attackers to conduct a padding oracle attack.

In Nimbus JOSE+JWT before 4.39, there is no integer-overflow check when converting length values from bytes to bits, which allows attackers to conduct HMAC bypass attacks by shifting Additional Authenticated Data (AAD) and ciphertext so that different plaintext is obtained for the same HMAC.