A timer found in the Shamoon cyber-sabotage malware discovered last week matches the exact time and date when a hacktivist group claims to have disabled thousands of computers from the network of Saudi Aramco, the national oil company of Saudi Arabia.
"We penetrated a system of Aramco company by using the hacked systems in several countries and then sent a malicious virus to destroy thirty thousand computers networked in this company," a group called the "Cutting Sword of Justice" said in a Pastebin post on August 15. "The destruction operations began on Wednesday, Aug 15, 2012 at 11:08 AM (Local time in Saudi Arabia) and will be completed within a few hours."
That same day, Saudi Aramco confirmed that some sectors of its computer network were affected by a computer virus that infected workstations used by its employees. However, the incident did not impact the oil production operations in any way, Aramco said at the time.
The news was followed by announcements from several antivirus vendors including Symantec, McAfee and Kaspersky Lab about the discovery of a new destructive piece of malware called Shamoon or Disttrack.
Shamoon contains a so-called wiper module designed to overwrite files from certain directories and the hard disk drive's Master Boot Record (MBR) - a special region of the disk that contains information about its partitions.
Given the similarities between Shamoon's functionality and the hacktivist group's description of the Aramco attack, there is speculation that the malware might be responsible for the Saudi Arabian company's recent computer problems.
Some other bits of information also pointed in this direction, like Symantec's statement that the malware was used in a targeted attack against an unnamed organisation from the energy sector or that a path string found inside the malware included a directory called "ArabianGulf."
However, the most convincing piece of evidence found so far consists of a timer that activates the malware's file and MBR wiping functionality.
"The dropper determines whether a specified date has come or not," Kaspersky Lab researcher Dmitry Tarakanov said earlier this week. "The hardcoded date is 15th August 2012 08:08 UTC."
This coincides with the exact time and date when the "Cutting Sword of Justice" hackers claimed the so-called destruction of Aramco computers began - Wednesday, Aug 15, 2012, at 11.08am local time in Saudi Arabia (UTC+3:00).
"This is only one indication that the events could possibly be related, and that's only if the Pastebin posting is legitimate," Kaspersky Lab chief security expert Alexander Gostev said. "At this time there is not enough concrete evidence to connect the two events."
Other details don't match up. For example, an internal network IP address used by the Shamoon samples analysed by antivirus vendors was not present in a list of Aramco internal IP addresses released in a separate Pastebin post by the hackers on August 17.
"This might mean that those samples are part of an attack on a different entity," said Aviv Raff, the chief technology officer at security firm Seculert. "Or, this is indeed part of the attack against Aramco, but the attackers decided not to share this IP address in the pastes."
In yet another Pastebin post, possibly by the same hackers, they threaten to attack Aramco a second time on Aug. 25 at 21:00 GMT, Raff said.
In its original announcement, the "Cutting Sword of Justice" hacktivist group said that it targeted Aramco because it is the main financial source for Saudi Arabia's Al Saud regime, which the group claims supported oppressive government actions in countries like Syria, Bahrain, Yemen, Lebanon or Egypt.
However, not everyone is convinced by its alleged anti-government-oppression agenda. "I've heard speculation from more than one source in Saudi Arabia that the malware attack against Saudi Aramco's network was an Iranian operation to discourage Saudi Armaco from increasing its oil production to compensate for Iran's decrease in oil deliveries due to sanctions imposed on it by the US and European Union," cybersecurity expert and analyst Jeffrey Carr said.
"Iran has been known to use its indigenous hacker population to run state-sponsored attacks in the past during Operation Cast Lead (Ashianeh Security Group)," Carr said. "Other well-known and highly skilled Iranian hackers include the Iranian Cyber Army and ComodoHacker."
"During our analysis of the Shamoon malware we noticed an error in the data comparison routine," Kaspersky's Gostev said. "In our experience, such programming errors are not commonly found in sophisticated cyber-weapons; however, we currently do not have enough tangible evidence to determine what type of threat actors or groups were behind Shamoon."
Back in April, computers from Iran's oil ministry were also attacked using a piece of malware with data-wiping functionality. That malware has never been identified, but Kaspersky Lab researchers concluded last week, based on known technical details, that Shamoon was most likely not involved in those attacks.
However, Shamoon might be a copycat of the wiper malware used in Iran that was created by hackers inspired by that incident, the Kaspersky researchers said at the time.