RUSTSEC-2020-0030: Missing sanitization in mozwire allows local file overwrite of files ending in .conf

What to do

1. See which version you have: cargo tree -i mozwire (it also shows which of your dependencies pulls it in).
2. Update within your version requirement: cargo update -p mozwire. If the fix is a newer major or minor than your requirement allows, raise it in Cargo.toml (for example mozwire = "0.4.2") or update the dependency that pulls it in.
3. Check again with cargo audit, or paste your Cargo.lock into our Cargo.toml checker.

Details from the advisory

The client software downloaded a list of servers from mozilla's servers and created local files named after the hostname field in the json document.

No verification of the content of the string was made, and it could therefore have included '../' leading to path traversal.

This allows an attacker in control of mozilla's servers to overwrite/create local files named .conf.

The flaw was corrected by sanitizing the hostname field.

References

• Package: crates.io/crates/mozwire
• Advisory: rustsec.org/advisories/RUSTSEC-2020-0030.html
• Report: github.com/NilsIrl/MozWire/issues/14

From the RustSec Advisory Database (CC0-1.0) via the OSV export, downloaded Oct 24, 2026. Severity score computed from the published CVSS vector.