Back in December, the SolarWinds supply chain attack made the headlines when a Russian cyber espionage group tampered with updates for SolarWinds’ Orion Network Management products that the IT company provides to government agencies, military, and intelligence offices.
Mimecast was one of SolarWinds customers that were impacted by the attack, its systems were infected with the Sunburst backdoor distributed through tainted Orion software updates.
Now the company admitted that hackers stole part of its source code from its repositories, but did not modified it.
Mimecast also added that the source code accessed by the hackers was incomplete and would be used to build and run any component of the Mimecast service.
“Using this entry point, the threat actor accessed certain Mimecast-issued certificates and related customer server connection information. The threat actor also accessed a subset of email addresses and other contact information, as well as encrypted and/or hashed and salted credentials. In addition, the threat actor accessed and downloaded a limited number of our source code repositories, but we found no evidence of any modifications to our source code nor do we believe there was any impact on our products.” reads the incident report published by mimecast. “We have no evidence that the threat actor accessed email or archive content held by us on behalf of our customers.”
Mimecast states that only a few customers who used the stolen certificate were targeted by the threat actor, it already notified them. The company urged customers hosted in the United States and United Kingdom to reset any server connection credentials in use on the Mimecast platform as a precautionary measure.
The company added that it is resetting the affected hashed and salted credentials as a precautionary step.
Below the list of additional remediation measures implemented by the company in response to the security incident:
You can find more details about the SolarWinds attack here.
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(SecurityAffairs – hacking, Solarwinds)