In jsonwebtoken node module before 4.2.2 it is possible for an attacker to bypass verification when a token digitally signed with an asymmetric key (RS/ES family) of algorithms but instead the attacker send a token digitally signed with a symmetric algorithm (HS* family).

Affected: npm: jsonwebtoken

Versions 4.2.1 and earlier of `jsonwebtoken` are affected by a verification bypass vulnerability. This is a result of weak validation of the JWT algorithm type, occuring when an attacker is allowed to arbitrarily specify the JWT algorithm.

## Recommendation

Update to version 4.2.2 or later.