ASUS says it has released a fix for the Live Update utility that threat actors abused in Operation ShadowHammer supply chain attack to deliver malware to hundreds of users.
Discovered by Kaspersky in January 2019, Operation ShadowHammer took place between June and November 2018 and leveraged the proprietary tool that comes pre-installed on ASUS notebooks. The attack remained hidden because the actors used a stolen certificate to sign the compromised software.
The ShadowHammer actors apparently targeted only 600 devices with a second-stage payload, although over one million are believed to have downloaded a backdoored version of the ASUS Live Update utility.
The attack was highly targeted, given the number of users who were served the next stage payload, but the security researchers couldn’t determine exactly what the actors behind the operation were after.
Following the initial reports on the incident, ASUS has confirmed that its users were infected through its compromised tool and says it has been reaching out to the affected users and has also provided assistance to help removing security risks.
“A small number of devices have been implanted with malicious code through a sophisticated attack on our Live Update servers in an attempt to target a very small and specific user group,” ASUS said in an emailed statement.
The computer maker also revealed that a fix has been included in the latest version (ver. 3.6.8) of the Live Update software, along with “multiple security verification mechanisms to prevent any malicious manipulation in the form of software updates or other means.”
The company also implemented an enhanced end-to-end encryption mechanism and updated and strengthened its server-to-end-user software architecture to ensure that similar attacks won’t happen again.
On top of that, ASUS has created an online security diagnostic tool that allows users to check whether their systems have been affected. “We encourage users who are still concerned to run it as a precaution,” ASUS says.
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