It injects a dll component into a running process of Skype. The Trojan can extract and save the video and audio data.

If a user’s machine is secured but the one whom he or she is talking to is not secured, then the Trojan can still steal the data of the conversation.

Based on the samples that Sophos has collected, both the executable and the injected dll component are detected as Troj/Skytap-Gen.

Source: Sophos