High (7.6) in auth0 jsonwebtoken. EPSS 0.6% chance of exploitation in the next 30 days. Fixed in jsonwebtoken 9.0.0.
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.
Severity
CVSS 3.1
7.6 high
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L
EPSS
0.6% chance of exploitation in the next 30 days; higher than 47% of CVEs (scores of 2026-10-31)