Kaseya Rules Out Supply-Chain Attack; Says VSA 0-Day Hit Its Customers Directly

U.S. technology firm Kaseya, which is firefighting the largest ever supply-chain ransomware strike on its VSA on-premises product, ruled out the possibility that its codebase was unauthorizedly tampered with to distribute malware.

While initial reports raised speculations that the ransomware gang might have gained access to Kaseya’s backend infrastructure and abused it to deploy a malicious update to VSA servers running on client premises, in a modus operandi similar to that of the devastating SolarWinds hack, it has since emerged that a never-before-seen security vulnerability (CVE-2021-30116) in the software was leveraged to push ransomware to Kaseya’s customers.

“The attackers were able to exploit zero-day vulnerabilities in the VSA product to bypass authentication and run arbitrary command execution,” the Miami-headquartered company noted in the incident analysis. “This allowed the attackers to leverage the standard VSA product functionality to deploy ransomware to endpoints. There is no evidence that Kaseya’s VSA codebase has been maliciously modified.”

In other words, while successful zero-day exploitation on Kaseya VSA software by itself isn’t a supply-chain attack,…