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Status published
Medium
CVE-2025-66220
Envoy’s TLS certificate matcher for `match_typed_subject_alt_names` may incorrectly treat certificates containing an embedded null byte
Vulnerability 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.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
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Affected Vendor
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View all reports →Affected Software
envoy
Vulnerable Versions:
>= 1.36.0, <= 1.36.2, >= 1.35.0, <= 1.35.6, >= 1.34.0, <= 1.34.10, <= 1.33.12
Timeline
Official Publish:
December 3rd, 2025
Last Modified:
December 3rd, 2025
Added to House:
July 22nd, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:L/A:N
Weaknesses (CWE)
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.