CVE-2026-47778
- Source
- https://cve.org/CVERecord?id=CVE-2026-47778
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-47778.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-47778
- Aliases
-
- BIT-envoy-2026-47778
- GHSA-f8x4-rw5x-f3r7
- Downstream
- Related
- Published
- 2026-06-26T17:27:57Z
- Modified
- 2026-08-12T03:51:48Z
- Severity
-
- 4.4 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N CVSS Calculator
- Summary
- Envoy: Embedded NUL in TLS DNS SAN Truncation in the Default TLS Certificate Validator. (Auth Bypass)
- Details
-
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.
- Database specific
{ "cna_assigner": "GitHub_M", "cwe_ids": [ "CWE-158" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47778.json" }- References
Affected packages
Git / github.com/envoyproxy/envoy
Affected ranges
- Type
- GIT
- Repo
- https://github.com/envoyproxy/envoy
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedFixedIntroducedFixedIntroducedFixedIntroducedFixed
- Database specific
-
Show details
{ "cpe": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*", "extracted_events": [ { "introduced": "0" }, { "fixed": "1.35.13" }, { "introduced": "1.36.0" }, { "fixed": "1.36.9" }, { "introduced": "1.37.0" }, { "fixed": "1.37.5" }, { "introduced": "1.38.0" }, { "fixed": "1.38.3" } ], "source": "CPE_RANGE" }