Name: CVE-2025-66220: Improper Null Termination
Creator: Rapid7
Published: 2025-12-03T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2025-66220, CWE-170, CVSS 7.1, EPSS 0.00168

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.

CVSS Details

CVSS 3.1 Base Score: 7.1
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Amazon Linux Ami 2	—	Upgrade ecs-service-connect-agent	May 20, 2026	May 20, 2026

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CVSS Details

Covered by Rapid7

Prioritise with Active Threat Intelligence