CVE-2023-27488 is a critical vulnerability in Envoy proxy versions prior to 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9. It allows for escalation of privileges when the ext_authz filter is configured with failure_mode_allow: true. An attacker can send HTTP headers with non-UTF-8 data, causing Envoy to generate an invalid protobuf message and potentially bypass authorization. This vulnerability has a CVSS score of 9.8 (Critical), indicating a severe risk with a network attack vector and low attack complexity, leading to high impacts on confidentiality, integrity, and availability. The primary impact is unauthorized access due to the failure_mode_allow setting, but it can also disrupt logging and visibility for other services. Currently, there is no evidence of active exploitation, and no public exploit code (Metasploit, Nuclei, ExploitDB) or significant community discussion has been identified. Organizations should prioritize patching to the recommended versions or implement the suggested workarounds to mitigate this risk.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 1.22.9CPE matchmatch criteria | cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* | ||
>= 1.23.0, < 1.23.6CPE matchmatch criteria | cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* | ||
>= 1.24.0, < 1.24.4CPE matchmatch criteria | cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* | ||
>= 1.25.0, < 1.25.3CPE matchmatch criteria | cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.