In the XZ Utils backdoor, Jia Tan's email address had zero trace even in breached DBs and all communication was routed through a foreign VPN. Has anyone made the effort to look for maintainers/contributors with similar profiles to see if there's any

From https://gigazine.net/gsc\_news/en/20240404-xz-utils-jia-tan/:

Brian Krebs writes that he could find “zero trace” of Jia Tan’s email address outside of the messages they sent to fellow open source contributors, even after scouring breached databases. Jia Tan also appears to have routed all their communications through a VPN with a Singaporean IP address.

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