Vulnerability Description
In Envoy before versions 1.12.6, 1.13.4, 1.14.4, and 1.15.0 when validating TLS certificates, Envoy would incorrectly allow a wildcard DNS Subject Alternative Name apply to multiple subdomains. For example, with a SAN of *.example.com, Envoy would incorrectly allow nested.subdomain.example.com, when it should only allow subdomain.example.com. This defect applies to both validating a client TLS certificate in mTLS, and validating a server TLS certificate for upstream connections. This vulnerability is only applicable to situations where an untrusted entity can obtain a signed wildcard TLS certificate for a domain of which you only intend to trust a subdomain of. For example, if you intend to trust api.mysubdomain.example.com, and an untrusted actor can obtain a signed TLS certificate for *.example.com or *.com. Configurations are vulnerable if they use verify_subject_alt_name in any Envoy version, or if they use match_subject_alt_names in version 1.14 or later. This issue has been fixed in Envoy versions 1.12.6, 1.13.4, 1.14.4, 1.15.0.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Envoyproxy | Envoy | < 1.12.6 |
Related Weaknesses (CWE)
References
- https://github.com/envoyproxy/envoy/security/advisories/GHSA-w5f5-6qhq-hhrgThird Party Advisory
- https://github.com/envoyproxy/envoy/security/advisories/GHSA-w5f5-6qhq-hhrgThird Party Advisory
FAQ
What is CVE-2020-15104?
CVE-2020-15104 is a vulnerability with a CVSS score of 4.6 (MEDIUM). In Envoy before versions 1.12.6, 1.13.4, 1.14.4, and 1.15.0 when validating TLS certificates, Envoy would incorrectly allow a wildcard DNS Subject Alternative Name apply to multiple subdomains. For ex...
How severe is CVE-2020-15104?
CVE-2020-15104 has been rated MEDIUM with a CVSS base score of 4.6/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2020-15104?
Check the references section above for vendor advisories and patch information. Affected products include: Envoyproxy Envoy.