Improper input validation in Envoyproxy Envoy

CVE-2023-27493

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.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.005 (41.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N.

Affected products

  • Envoyproxy Envoy — versions >= 1.25.0, < 1.25.3, >= 1.24.0, < 1.24.4, >= 1.23.0, < 1.23.6

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2023-27493?
CVE-2023-27493 is a high-severity vulnerability in Envoyproxy Envoy, classified under Improper Input Validation. CVSS score: 8.1/10. Published 2023-04-04.
How severe is CVE-2023-27493?
High severity. CVSS v3 base score is 8.1 out of 10.