The Terror exploit kit (EK) updated to the point where it can fingerprint victims and target specific vulnerabilities, researchers said.
Terror ended up initially discovered in January, when security researchers found it was targeting vulnerabilities with exploits taken from Metasploit or from either Sundown or Hunter EKs, said researchers at Talos.
Terror activity increased last month, after the Sundown EK inexplicably disappeared from the threat landscape.
Previously, the exploit kit was going after victims with exploits at the same time, even if those exploits didn’t match the targeted browser environment.
The threat has now added more exploits and is fingerprinting victim’s system to determine what exploit would be successful based on operating system, patch level, browser version, and installed plugins.
The use of more targeted exploits makes it more difficult for investigators to determine which exploits the toolkit has. However, “it is interesting to note that the adversaries are using an URL parameter in cleartext for the vulnerability they are going to exploit,” Talos researchers said.
Talos researchers also identified a potentially compromised legitimate web site that appears to be operating as a malware gate. Initially redirecting visitors to a RIG landing page, the gate switched to Terror after one day.