IBM WebSphere Application Server (WAS) 6.1 before 6.1.0.39 and 7.0 before 7.0.0.17 uses a weak WS-Security XML encryption algorithm, which makes it easier for remote attackers to obtain plaintext data from a (1) JAX-RPC or (2) JAX-WS Web Services request via unspecified vectors related to a "decryption attack."