CVE-2023-27493

Envoy doesn't escape HTTP header values

State: Published
Severity: 8.1 High
Published: Apr 4, 2023
Updated: Feb 11, 2025
Reserved: Mar 1, 2023

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, Envoy does not sanitize or escape request properties when generating request headers. This can lead to characters that are illegal in header values to be sent to the upstream service. In the worst case, it can cause upstream service to interpret the original request as two pipelined requests, possibly bypassing the intent of Envoy’s security policy. Versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9 contain a patch. As a workaround, disable adding request headers based on the downstream request properties, such as downstream certificate properties.

Scores

CVSS	Score	Vector	Source
3.1	8.1 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N	GitHub_M

Weaknesses

CWE-20 Improper Input Validation

Affected Products

Product	Versions
envoyenvoyproxy	>= 1.25.0, < 1.25.3Affected >= 1.24.0, < 1.24.4Affected >= 1.23.0, < 1.23.6Affected < 1.22.9Affected

References

https://github.com/envoyproxy/envoy/security/advisories/GHSA-w5w5-487h-qv8q

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