PT-2026-52887 · Undefined · Undefined
Published
2026-06-26
·
Updated
2026-06-26
·
CVE-2026-47778
CVSS v3.1
4.4
Medium
| Vector | AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N |
Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1, a structural flaw was identified in DefaultCertValidator::verifySubjectAltName where the extracted DNS SAN string is cast to a C-style string using .c str() before being passed to the Utility::dnsNameMatch() algorithm. If the attacker serves a certificate with a dNSName SAN containing an embedded NUL byte, the helper Utility::generalNameAsString captures the complete string including the NUL. However, when .c str() evaluates it, implicit conversion to absl::string view inside dnsNameMatch relies on strlen(), prematurely truncating the evaluation context. Envoy evaluates trucated string against the exact required config san match and returns true, thereby successfully validating the string with the Nul byte for an upstream routing. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1.
Fix
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Weakness Enumeration
Related Identifiers
Affected Products
Undefined