Vulnerability Report: GO-2023-2379

• CVE-2023-49290, GHSA-7f9x-gw85-8grf
• Affects: github.com/lestrrat-go/jwx, github.com/lestrrat-go/jwx/v2
• Published: Dec 11, 2023

The JWE key management algorithms based on PBKDF2 require a JOSE Header Parameter called p2c (PBES2 Count). This parameter dictates the number of PBKDF2 iterations needed to derive a CEK wrapping key. Its purpose is to intentionally slow down the key derivation function, making password brute-force and dictionary attacks more resource-intensive. However, if an attacker sets the p2c parameter in JWE to a very large number, it can cause excessive computational consumption.