title: Crash when a cluster is deleted in Envoy
description: Envoy is an open source edge and service proxy, designed for cloud-native applications. When a cluster is deleted via Cluster Discovery Service (CDS) all idle connections established to endpoints in that cluster are disconnected. A recursion was introduced in the procedure of disconnecting idle connections that can lead to stack exhaustion and abnormal process termination when a cluster has a large number of idle connections. This infinite recursion causes Envoy to crash. Users are advised to upgrade.
problem types: CWE-674: Uncontrolled Recursion
affected:
{
product: envoy
vendor: envoyproxy
versions:
status: affected, version: >= 1.20.0, < 1.20.2
status: affected, version: >= 1.21.0, < 1.21.1
}
metrics:
cvssV3_1: [
attackComplexity: HIGH
attackVector: NETWORK
availabilityImpact: HIGH
baseScore: 4.4
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: HIGH
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
version: 3.1
]