CVE-2023-27491

Envoy is an open source edge and service proxy designed for cloud-native applications. Compliant HTTP/1 service should reject malformed request lines. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, There is a possibility that non compliant HTTP/1 service may allow malformed requests, potentially leading to a bypass of security policies. This issue is fixed in versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9.

• CWE-20
• CWE-444

• https://datatracker.ietf.org/doc/html/rfc9113#section-8.3Not Applicable
• https://datatracker.ietf.org/doc/html/rfc9114#section-4.3.1Not Applicable
• https://github.com/envoyproxy/envoy/security/advisories/GHSA-5jmv-cw9p-f9rpExploit, Vendor Advisory
• https://www.rfc-editor.org/rfc/rfc9110#section-5.6.2Not Applicable
• https://datatracker.ietf.org/doc/html/rfc9113#section-8.3Not Applicable
• https://datatracker.ietf.org/doc/html/rfc9114#section-4.3.1Not Applicable
• https://github.com/envoyproxy/envoy/security/advisories/GHSA-5jmv-cw9p-f9rpExploit, Vendor Advisory
• https://www.rfc-editor.org/rfc/rfc9110#section-5.6.2Not Applicable

Published

Apr 4, 2023

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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