Add malware advisory for exploration

crates/exploration/RUSTSEC-0000-0000.md

@@ -0,0 +1,23 @@
+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "exploration"
+date = "2026-06-02"
+expect-deleted = true
+categories = ["malicious"]
+
+[versions]
+patched = []
+```
+
+# `exploration` was removed from crates.io for malicious code
+
+A method within the `exploration` crate attempted to download and execute a
+payload from a remote site.
+
+The malicious crate had 1 version published on 2026-06-02, approximately 1 hour
+before removal, and had no evidence of actual usage. This crate had no
+dependencies on crates.io.
+
+Thanks to Kirill Boychenko from the [Socket Threat Research
+Team](https://socket.dev/) for reporting this crate.