Latest research by BAE Systems Applied Intelligence has shed more light on the Snake cyber espionage toolkit.
The security company found the malware has been in development since at least 2005 and the architecture has have evolved since then.
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BAE Systems Applied Intelligence managing director, Martin Sutherland, said the malware makes use of tricks to overcome Windows security and is able to hide intrusions from traditional defensive tools.
"What this research once more demonstrates is how organised and well-funded adversaries are using highly sophisticated tools and techniques to target legitimate organisations on a massive scale," he said.
There were suspicions around the existence of the Snake malware for some time, though Sutherland said it was only now the full scale of its capabilities and the threat it presents are fully understood.
Year of the snake
The complexity of the malware also alludes to the commitment and financial preparedness of Snake's authors and operators.
Sutherland said the range of variants and techniques used to support the malware also stood out.
"The threat really does raise the bar in terms of what potential targets, and the security community in general, have to do to keep ahead of cyber attackers," he said.
As for what future implications Snake has, Sutherland expects keeping confidential information safe to remain a challenge for "many years to come."
Patrick Budmar covers consumer and enterprise technology breaking news for IDG Communications. Follow Patrick on Twitter at @patrick_budmar.