Debian Rust Security Tracker 🩺🦀

RUSTSEC-2026-0099: Name constraints were accepted for certificates asserting a wildcard name

1 affected
Crate
rustls-webpki
Patched Versions
>=0.103.12, <0.104.0-alpha.1
>=0.104.0-alpha.6
Debian Version
0.103.15+ds-1
0.101.7-7
Debian Bugs
—
Issued
2026-04-14
Aliases
CVE-2026-93601
GHSA-xgp8-3hg3-c2mh
Patched:Affected

Permitted subtree name constraints for DNS names were accepted for certificates asserting a wildcard name.

This was incorrect because, given a name constraint of accept.example.com, *.example.com could feasibly allow a name of reject.example.com which is outside the constraint. This is very similar to CVE-2025-61727.

Since name constraints are restrictions on otherwise properly-issued certificates, this bug is reachable only after signature verification and requires misissuance to exploit.

This vulnerability is identified as GHSA-xgp8-3hg3-c2mh. Thank you to @1seal for the report.

Affected Packages

affected ⚠️ librust-rustls-webpki-0.101-dev 0.101.7-7