Vulnerabilities > CVE-2016-10555 - Cryptographic Issues vulnerability in Jwt-Simple Project Jwt-Simple 0.1.0/0.2.0/0.3.0

047910
CVSS 6.5 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
NONE
Integrity impact
HIGH
Availability impact
NONE
network
low complexity
jwt-simple-project
CWE-310

Summary

Since "algorithm" isn't enforced in jwt.decode()in jwt-simple 0.3.0 and earlier, a malicious user could choose what algorithm is sent sent to the server. If the server is expecting RSA but is sent HMAC-SHA with RSA's public key, the server will think the public key is actually an HMAC private key. This could be used to forge any data an attacker wants.

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Signature Spoofing by Key Recreation
    An attacker obtains an authoritative or reputable signer's private signature key by exploiting a cryptographic weakness in the signature algorithm or pseudorandom number generation and then uses this key to forge signatures from the original signer to mislead a victim into performing actions that benefit the attacker.