MEDIUM🇵🇱 Wersja polska

CVE-2026-47778

CVSS 4.4v3.1pub. 2026-06-26upd. 2026-06-29

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.

CVSS Vector
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N
  • Envoyproxy Envoy

    APP
    Envoyproxy
    < 1.35.131.36.0 – 1.36.9 (bez)1.37.0 – 1.37.5 (bez)1.38.0 – 1.38.3 (bez)
🔵
CHECK WITH VENDOR
No clear patch data available. Check vendor references.
CWE
References

Related vulnerabilities

CVE-2022-29226CRITICAL10.0ten sam produkt

Envoy is a cloud-native high-performance proxy. In versions prior to 1.22.1 the OAuth filter implementation do...

CVE-2019-18801CRITICAL9.8ten sam produkt

An issue was discovered in Envoy 1.12.0. An untrusted remote client may send HTTP/2 requests that write to the...

CVE-2019-18802CRITICAL9.8ten sam produkt

An issue was discovered in Envoy 1.12.0. An untrusted remote client may send an HTTP header (such as Host) wit...

CVE-2023-44487HIGH7.5⚠ KEVten sam produkt

The HTTP/2 protocol allows a denial of service (server resource consumption) because request cancellation can ...

CVE-2026-47220HIGH7.5ten sam produkt

Envoy is an open source edge and service proxy designed for cloud-native applications. From 1.37.0 until 1.37....