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

Huawei Quidway S9700 V200R003C00SPC500, Quidway S9300 V200R003C00SPC500, Quidway S7700 V200R003C00SPC500, Quidway S6700 V200R003C00SPC300, Quidway S6300 V200R003C00SPC300, Quidway S5700 V200R003C00SPC300, Quidway S5300 V200R003C00SPC300 enable attackers to launch DoS attacks by crafting and sending malformed packets to these vulnerable products.

Huawei AR routers with software before V200R007C00SPC100; Quidway S9300 routers with software before V200R009C00; S12700 routers with software before V200R008C00SPC500; S9300, Quidway S5300, and S5300 routers with software before V200R007C00; and S5700 routers with software before V200R007C00SPC500 make it easier for remote authenticated administrators to obtain and decrypt passwords by leveraging selection of a reversible encryption algorithm.

Huawei AR routers with software before V200R007C00SPC100; Quidway S9300 routers with software before V200R009C00; S12700 routers with software before V200R008C00SPC500; S9300, Quidway S5300, and S5300 routers with software before V200R007C00; and S5700 routers with software before V200R007C00SPC500 makes it easier for remote authenticated administrators to obtain encryption keys and ciphertext passwords via vectors related to key storage.