CVE-2025-66220: Envoy's TLS certificate matcher for `match_typed_subject_alt_names` may incorrectly treat certificates containing an embedded null byte

December 5, 2025

Envoy’s mTLS certificate matcher for match_typed_subject_alt_names may incorrectly treat certificates containing an embedded null byte (\0) inside an OTHERNAME SAN value as valid matches.

References

github.com/advisories/GHSA-rwjg-c3h2-f57p
github.com/envoyproxy/envoy
github.com/envoyproxy/envoy/security/advisories/GHSA-rwjg-c3h2-f57p
nvd.nist.gov/vuln/detail/CVE-2025-66220

Code Behaviors & Features

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