Apache WSS4J: Unauthenticated denial of service via integer overflow in DER parsing of X.509 certificate extensions

An integer overflow in WSS4J's DER bounds check lets an oversized allocation pass validation. An unauthenticated attacker can send a SOAP message carrying an X.509 certificate whose SubjectKeyIdentifier extension declares a length of 0x7FFFFFFF; WSS4J decodes this while resolving the signature's key reference, before the message is authenticated, so an eleven-byte extension triggers a 2 GB allocation. Repeated requests exhaust server memory. Users are recommended to upgrade to versions 4.0.2 or 3.0.6 or 2.4.4, which fix this issue.