Malicious network activity has been detected that could indicate the presence of a command-and-control system across multiple devices.
Description
Malicious network activity has been detected that could indicate the presence of a trojan command-and-control system infection in an affected internal network. Command-and-control communications could point towards a possible Advanced Persistent Threat attempt.
A typical command-and-control system consists of a trojan server program and a client domain that implement multiple callback communication domains. The callback domains provide redundancy and are resolved in the trusted Domain Name System (DNS) protocol. On most occasions, the DNS registration information of the callback domains and subdomains bears a resemblance to that of a legitimate domain. After this initialization, further communication between the command-and-control network takes place via protocols such as HTTP. This communication could be encrypted or compressed and, when decrypted or decompressed, contain sensitive information about the infected machines. Compression methods popularly used are DEFLATE, Base64 and the ZLIB Compressed Data Format Specification. Certain command-and-control networks could use the SSL protocol and a compromised digital certificate to encrypt the data communication streams.
The command-and-control trojan server could allow an attacker to start a command shell, terminate processes and services, upload and download files, control TCP connections, manipulate user accounts, retrieve system information, log user activity, steal browser cookies, transmit socially engineered e-mail messages, conduct process injections, conduct denial of service (DoS) attacks, and shutdown or restart the computer. It could also include rootkit functionality and be resilient to antivirus software.
Reports suggest that Advanced Persistent Threat attacks were initiated against RSA (a Security Division of EMC) and McAfee Labs networks.
Administrators are advised to implement an intrusion prevention system (IPS) or intrusion detection system (IDS) to help detect and prevent attacks that attempt to exploit this vulnerability.
Signatures
Cisco Systems Cisco Intrusion Prevention System (IPS) 6.0
The security vulnerability applies to the following combinations of products.
Primary Products:
IntelliShield
Security Activity Bulletin
Original Release Base
Associated Products:
N/A
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