We identified that proc-macro-en contained the same build script as proc-macro1 and it was part of the same supply chain attack.

This crate had one single version published at 2026-08-20. The crate was removed from crates.io and related user account was locked.

This crate was used as part of a malware campaign targeted at users of arrayref, which was downloaded 2,285 times before being removed; see the arrayref advisory for more detail.