`tracings` was removed from crates.io for malicious code

Summary

This is part of an ongoing campaign to attempt to typosquat crates in an attempt to exfiltrate Polymarket credentials.

The malicious crate had 1 version published on 2026-02-26 approximately 9 hours before removal and had no evidence of actual usage. The only crate depending on this crate was the `tracing_checks` crate, which was also part of this campaign and has received a separate advisory.

Thanks to Marko Ćupić for finding and reporting this to the Rust security response working group, and to Emily Albini for co-ordinating with the crates.io team.

The crates.io team advises anyone developing with Polymarket to review dependencies carefully. We are investigating ways to mitigate this attacker who appears to be very motivated to steal Polymarket credentials.