“Today is June 24th, 2012. It's Stuxnet's kill date. Stuxnet was programmed to stop replicating today,” F-Secure’s chief researcher Mikko Hypponen wrote on Twitter on Sunday.
Stuxnet’s main installer, which infected the core target, Siemens Simatic 'Step 7' projects, checked for key dates on these systems. Dates were used as markers to determine when not to infect a machine, Symantec noted in its 2011 whitepaper on the malware.
The June 24, 2012 ‘kill date’, as <i>Christian Science Monitor</i> pointed out, is the seven year anniversary of Iran’s president Mahmoud Ahmadinejad.
Another ‘do not infect’ marker was May 9, 1979, the date of the execution of Habib Elghanian, an Iranian Jew whose killing sparked an exodus of the Iranian Jewish community, Symantec pointed out.
The malware was confirmed earlier this month by unnamed US officials to be the product of a program code-named Olympic Games, begun under the Bush Administration, accelerated by US President Barack Obama and contributed to by an Israeli military cyber team.
It is one of three known pieces of malware security researchers believe were likely developed by the same authors, including the more recently discovered but older malware, Flame and so-called ‘son of Stuxnet’, Duqu.
Discovered by security vendors in mid-2010, Stuxnet’s timeline traced back to 2008 when the first small attack was launched under then US President George W. Bush.
Obama ‘sped‘ the program up and oversaw three main waves that Symantec had on record between June 2009 and April 2010.
By July 29 2010 there were at least 100,000 hosts infected by Stuxnet, 60,000 of which were inside Iran, according to Symantec’s analysis of Stuxnet command and control traffic. Major infections also occurred in India and Indonesia, likely the result of Stuxnet’s propagation methods.
Stuxnet exploited five key Windows flaws and was aimed primarily at Iran’s Natanz uranium enrichment facility, which it achieved by sabotaging a Siemens program logic controller with a rootkit.
One of its key methods of tunnelling deeper into its target environment was by exploiting an LNK vulnerability to compromise removable drives, which are often used in industrial environments to move data to special devices that are never connected to an untrusted network.
Stuxnet’s drivers were signed by valid certificates, the first one belonging to Realtek Semiconductor Corps, and a second driver after the first was invalidated, with JMicron Technology Group.