Answer in brief
CVE-2026-47778 records a Medium severity (CVSS 4.4) security vulnerability in CVE-2026-47778. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
Review the upstream advisory, identify the affected product in your inventory, and apply the vendor update when one is available.
Vulnerability describes the vulnerability class recorded for this advisory. The current record does not mark CVE-2026-47778 as known exploited; continue to monitor the source for status changes. This is a product-level record in the current feed, not a package-level dependency mapping.
Affected software not mapped. Review the upstream record for vendor-specific product and version guidance.
Answer in brief
CVE-2026-47778 records a Medium severity (CVSS 4.4) security vulnerability in CVE-2026-47778. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
Review the upstream advisory, identify the affected product in your inventory, and apply the vendor update when one is available.
Vulnerability describes the vulnerability class recorded for this advisory. The current record does not mark CVE-2026-47778 as known exploited; continue to monitor the source for status changes. This is a product-level record in the current feed, not a package-level dependency mapping.
Affected software not mapped. Review the upstream record for vendor-specific product and version guidance.
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.
Reported by NVD (nvd).
CVE-2026-47778 records a Medium severity (CVSS 4.4) security vulnerability in CVE-2026-47778. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
The source record does not mark it as known exploited.
Confirm whether the product or interface named by this advisory exists in your inventory.
HOL Guard can help your team monitor supply-chain activity while the upstream record is clarified.
Explore HOL GuardEnvoy 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.
Reported by NVD (nvd).
CVE-2026-47778 records a Medium severity (CVSS 4.4) security vulnerability in CVE-2026-47778. The source record does not mark it as known exploited. No package mapping is present, so exposure must be confirmed against the affected product and deployment inventory.
The source record does not mark it as known exploited.
Confirm whether the product or interface named by this advisory exists in your inventory.
HOL Guard can help your team monitor supply-chain activity while the upstream record is clarified.
Explore HOL Guard