The infection was discovered when a computer user attempted to visit the affected website, and received a warning message that a file on the site was infected by code which attempts to exploit the vulnerability in Microsoft XML Core Services which could allow Remote Code Execution (CVE-2012-1889).
According to security researcher Graham Cluley, "We know that a tried-and-trusted method of hacking into large companies and organisations is to target the supply chain. The theory goes that rather than try to hack a company which may have robust security practices and security teams, the bad actor can instead attack a smaller supplier who are less well placed to notice the security breach."
Sophos which identified the security breach, has declined to name the company involved — but has raised its threat level to "Critical"."
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