The Fujitsu TLS library allows a man-in-the-middle attack. This affects Interstage Application Development Cycle Manager V10 and other versions, Interstage Application Server V12 and other versions, Interstage Business Application Manager V2 and other versions, Interstage Information Integrator V11 and other versions, Interstage Job Workload Server V8, Interstage List Works V10 and other versions, Interstage Studio V12 and other versions, Interstage Web Server Express V11, Linkexpress V5, Safeauthor V3, ServerView Resource Orchestrator V3, Systemwalker Cloud Business Service Management V1, Systemwalker Desktop Keeper V15, Systemwalker Desktop Patrol V15, Systemwalker IT Change Manager V14, Systemwalker Operation Manager V16 and other versions, Systemwalker Runbook Automation V15 and other versions, Systemwalker Security Control V1, and Systemwalker Software Configuration Manager V15.
It was discovered that the Invariance Weakness of the RC4 stream cipher could be used to recover plaintext from a TLS connection, when RC4 encryption is used.
"The Invariance Weakness is an L-shape key pattern in RC4 keys, which once it exists in an RC4 key, preserves part of the state permutation intact throughout the initialization process. This intact part includes the least significant bits of the permutation, when processed by the PRGA algorithm, determines the least significant bits of the allegedly pseudo-random output stream along a long prefix of the stream."
This can lead to significant leakage of plaintext bytes from the ciphertext.
External Reference:
http://www.imperva.com/docs/HIIAttackingSSLwhenusingRC4.pdf
A new attack was discovered against TLS that allows an attacker to recover a limited amount of plaintext from a TLS connection when RC4 encryption is used. The attacks arise from statistical flaws in the keystream generated by the RC4 algorithm which become apparent in TLS ciphertexts when the same plaintext is repeatedly encrypted at a fixed location across many TLS sessions.
Reference:
http://www.isg.rhul.ac.uk/tls/ http://blog.cryptographyengineering.com/2013/03/attack-of-week-rc4-is-kind-of-broken-in.html