Signature Validation Bypass in jsonwebtoken Library (<=8.5.1) due to Defaulting to None Algorithm

CVE-2022-23540 · HIGH Severity

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L

In versions `<=8.5.1` of `jsonwebtoken` library, lack of algorithm definition in the `jwt.verify()` function can lead to signature validation bypass due to defaulting to the `none` algorithm for signature verification. Users are affected if you do not specify algorithms in the `jwt.verify()` function. This issue has been fixed, please update to version 9.0.0 which removes the default support for the none algorithm in the `jwt.verify()` method. There will be no impact, if you update to version 9.0.0 and you don’t need to allow for the `none` algorithm. If you need 'none' algorithm, you have to explicitly specify that in `jwt.verify()` options.

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