CVE-2025-66220
Medium
Description
Envoy is a high-performance edge/middle/service proxy. In 1.33.12, 1.34.10, 1.35.6, 1.36.2, and earlier, 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.
SeverityMedium
CVSS5.0
Exploit probability—
Product
Envoy
PublishedDec 3, 2025
First seenDec 3, 2025
Weakness typeCWE-170CWE-170
How to fix
Update
- envoyproxy envoy1.33.13, 1.34.11, 1.35.7, 1.36.3 or later
- github.com/envoyproxy/envoy1.36.3, 1.35.7, 1.34.11, 1.33.13 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| envoyproxy envoy | v < 1.33.13, 1.34.0 ≤ v < 1.34.11, 1.35.0 ≤ v < 1.35.7, 1.36.0 ≤ v < 1.36.3 | 1.33.13, 1.34.11, 1.35.7, 1.36.3 |
| github.com/envoyproxy/envoyGo | 1.36.0 ≤ v < 1.36.3, 1.35.0 ≤ v < 1.35.7, 1.34.0 ≤ v < 1.34.11, v < 1.33.13 | 1.36.3, 1.35.7, 1.34.11, 1.33.13 |
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