Vulnerability Description
rustls-webpki (the Rust webpki fork used by rustls) versions >= 0.101.0 and prior to 0.103.12 and 0.104.0-alpha.6 incorrectly accepted permitted-subtree DNS name constraints for certificates asserting a wildcard name. For example, a name constraint of accept.example.com was treated as satisfied by a certificate for *.example.com, which could feasibly assert reject.example.com — a name outside the permitted subtree. Because name constraints are restrictions applied to otherwise properly issued certificates, the issue is only reachable after signature verification succeeds and requires a misissued wildcard certificate to exploit.
CVSS Score
LOW
Related Weaknesses (CWE)
References
- https://github.com/rustls/webpki/security/advisories/GHSA-xgp8-3hg3-c2mh
- https://www.vulncheck.com/advisories/rustls-webpki-0.101.0-before-0.103.12-name-
FAQ
What is CVE-2026-93601?
CVE-2026-93601 is a vulnerability with a CVSS score of 2.2 (LOW). rustls-webpki (the Rust webpki fork used by rustls) versions >= 0.101.0 and prior to 0.103.12 and 0.104.0-alpha.6 incorrectly accepted permitted-subtree DNS name constraints for certificates asserting...
How severe is CVE-2026-93601?
CVE-2026-93601 has been rated LOW with a CVSS base score of 2.2/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-93601?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.