CVE-2025-66220: Envoy’s TLS certificate matcher for `match_typed_subject_alt_names` may incorrectly treat certificates containing an embedded null byte
envoyproxy · envoy
Affected: envoyproxy · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 7% of scored CVEs
DescriptionCVE.org
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.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- envoyproxy · envoy>= 1.36.0, <= 1.36.2; >= 1.35.0, <= 1.35.6; >= 1.34.0, <= 1.34.10; <= 1.33.12
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- envoyproxy
- Published
- December 2025
CoverageNo articles yet
No CyberSIXT article names CVE-2025-66220 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.