CVE-2026-47778

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.

• CWE-158

• https://github.com/envoyproxy/envoy/security/advisories/GHSA-f8x4-rw5x-f3r7Exploit, Vendor Advisory, Mitigation
• https://github.com/envoyproxy/envoy/security/advisories/GHSA-f8x4-rw5x-f3r7Exploit, Vendor Advisory, Mitigation

Published

Jun 26, 2026

Last Modified

Jun 29, 2026

Status

Analyzed

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2026-47769APIFold reads an OpenAPI 3.x or Swagger 2.x specification an…5.3
• CVE-2026-4777A security flaw has been discovered in SourceCodester Sales …6.5
• CVE-2026-47770jq is a command-line JSON processor. Prior to 1.8.2, compari…5.5
• CVE-2026-47774Envoy is an open source edge and service proxy designed for …7.5
• CVE-2026-47775Envoy is an open source edge and service proxy designed for …6.8
• CVE-2026-47777Mastodon is a free, open-source social network server based …7.5
• CVE-2026-4778A weakness has been identified in SourceCodester Sales and I…6.5
• CVE-2026-47781PDM is a Python package and dependency manager. In versions …8.4
• CVE-2026-47782Android App "RoboForm Password Manager" provided by Siber Sy…4.6
• CVE-2026-47783In memcached before 1.6.42, username data for SASL password …8.1
• CVE-2026-47784In memcached before 1.6.42, password data for SASL password …8.1
• CVE-2026-4779A security vulnerability has been detected in SourceCodester…8.8