CVE-2026-26308 (GCVE-0-2026-26308)
Vulnerability from cvelistv5
Published
2026-03-10 19:01
Modified
2026-03-10 20:12
CWE
  • CWE-863 - Incorrect Authorization
Summary
Envoy is a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, the Envoy RBAC (Role-Based Access Control) filter contains a logic vulnerability in how it validates HTTP headers when multiple values are present for the same header name. Instead of validating each header value individually, Envoy concatenates all values into a single comma-separated string. This behavior allows attackers to bypass RBAC policies—specifically "Deny" rules—by sending duplicate headers, effectively obscuring the malicious value from exact-match mechanisms. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.
Impacted products
Vendor Product Version
envoyproxy envoy Version: >= 1.37.0, < 1.37.1
Version: >= 1.36.0, < 1.36.5
Version: >= 1.35.0, < 1.35.9
Version: < 1.34.13
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Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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