Abstract: Exploit nonspecific host intrusion prevention/detection methods, systems and smart filters are described. Portion of network traffic is captured and searched for a network traffic pattern, comprising: searching for a branch instruction transferring control to a first address in the memory; provided the first instruction is found, searching for a subroutine call instruction within a first predetermined interval in the memory starting from the first address and pointing to a second address in the memory; provided the second instruction is found, searching for a third instruction at a third address in the memory, located at a second predetermined interval from the second address; provided the third instruction is a fetch instruction, indicating the presence of the exploit; provided the third instruction is a branch instruction, transferring control to a fourth address in the memory, and provided a fetch instruction is located at the fourth address, indicating the presence of the exploit.

Abstract: An intrusion prevention/detection system filter (IPS filter) performance evaluation is provided. The performance evaluation is performed at both the security center and at the customer sites to derive a base confidence score and local confidence scores. Existence of new vulnerability is disclosed and its attributes are used in the generation of new IPS filter or updates. The generated IPS filter is first tested to determine its base confidence score from test confidence attributes prior to deploying it to a customer site. A deep security manager and deep security agent, at the customer site, collect local confidence attributes that are used for determining the local confidence score. The local confidence score and the base confidence score are aggregated to form a global confidence score. The local and global confidence scores are then compared to deployment thresholds to determine whether the IPS filter should be deployed in prevention or detection mode or sent back to the security center for improvement.

Abstract: There is described an electronic data communication system in which encrypted mail messages for a recipient are sent in two parts: message data encrypted by a symmetric encryption algorithm using a session key and session key data encrypted by an asymmetric encryption algorithm using a public key associated with the recipient. If the recipient uses a webmail service to access the encrypted electronic mail message, the encrypted session key data is sent to a trusted third party server which has access to the private key of the user. The trusted third party server decrypts the encrypted session key using the private key of the user, and then sends the decrypted session key to a remote network device for decryption of the encrypted message.