CVE-2024-23326: exploitation status and patch state

CVE-2024-23326 · CVSS 5.9 MEDIUM · EPSS <1%

Envoy is a cloud-native, open source edge and service proxy. A theoretical request smuggling vulnerability exists through Envoy if a server can be tricked into adding an upgrade header into a response. Per RFC https://www.rfc-editor.org/rfc/rfc7230#section-6.7 a server sends 101 when switching protocols. Envoy incorrectly accepts a 200 response from a server when requesting a protocol upgrade, but 200 does not indicate protocol switch. This opens up the possibility of request smuggling through Envoy if the server can be tricked into adding the upgrade header to the response.

Is CVE-2024-23326 exploited?

Which products and versions are affected?

No affected package list recorded here yet.

Is there a patch?

No patch identifier recorded here yet.

What PlainSec published about CVE-2024-23326

Primary sources

What this record does not say

KEV and EPSS are re-checked daily. Record last updated 2026-08-15.