CVE-2025-66220

low-risk
Published 2025-12-03

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.

Do I need to act?

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0.00% chance of exploitation
EPSS score — low exploit probability
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Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
5
CVSS 5.0/10 Medium
NETWORK / HIGH complexity

Affected Products (1)

Affected Vendors

21
/ 100
low-risk
Severity 16/34 · Moderate
Exploitability 0/34 · Minimal
Exposure 5/34 · Minimal