CVE-2017-18239: Authentikat-Jwt Project Authentikat-Jwt

Critical severity, CVSS 9.8. EPSS: 2% chance of exploitation in the next 30 days.

A time-sensitive equality check on the JWT signature in the JsonWebToken.validate method in main/scala/authentikat/jwt/JsonWebToken.scala in authentikat-jwt (aka com.jason-goodwin/authentikat-jwt) version 0.4.5 and earlier allows the supplier of a JWT token to guess bit after bit of the signature by repeating validation requests.

Affected products

• Authentikat-Jwt Project Authentikat-Jwt: up to and including 0.4.5

Published 2018-03-18. Last modified 2026-06-17.