TI-2022-07659 Aliases CVE-2022-23606

Crash when a cluster is deleted in Envoy

LOW 31CWE-674Published 2022-02-22 · Updated 2025-04-23

Key facts

Attack vector: Network
Privileges required: Low
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-674.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.01016 63rd percentileScored 2026-11-07

Fix Fixed envoy (envoyproxy): 1.20.2, 1.21.1Red Hat: 2 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
envoyproxy	envoy	1.20.0 to before 1.20.2; 1.21.0 to before 1.21.1	1.20.2, 1.21.1	Patch available	CNA

envoy Vendorenvoyproxy Affected 1.20.0 to before 1.20.2; 1.21.0 to before 1.21.1 Fixed in 1.20.2, 1.21.1 Patch available CNA

CPE configurations NVD · 2

CPE	Versions	Role	Vendor
cpe:2.3:a:envoyproxy:envoy::::::::	1.20.0 to before 1.20.2	Vulnerable	envoyproxy
cpe:2.3:a:envoyproxy:envoy:1.21.0:::::::*	1.21.0	Vulnerable	envoyproxy

cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:* Versions 1.20.0 to before 1.20.2 Vulnerable ·envoyproxy
cpe:2.3:a:envoyproxy:envoy:1.21.0:*:*:*:*:*:*:* Versions 1.21.0 Vulnerable ·envoyproxy

Remediation

Fix · CNA envoy (envoyproxy) Fixed in 1.20.2, 1.21.1

Red Hat 2 advisories

RHSA-2022:1275 Released 2022-04-07 · Red Hat rating Important
Red Hat OpenShift Service Mesh 2.1.2 security update
- OpenShift Service Mesh 2.1 servicemesh-2.1.2-4.el8, servicemesh-cni-2.1.2-4.el8, servicemesh-pilot-agent-2.1.2-4.el8 +3
RHSA-2022:1276 Released 2022-04-07 · Red Hat rating Important
Red Hat OpenShift Service Mesh 2.0.9 security update
- OpenShift Service Mesh 2.0 kiali-v1.24.7.redhat1-1.el8, servicemesh-2.0.9-3.el8, servicemesh-istioctl-2.0.9-3.el8 +6

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Product	Status	Plan or fix
OpenShift Service Mesh 2.0	Fixed	RHSA-2022:1276
OpenShift Service Mesh 2.1	Fixed	RHSA-2022:1275

Not affected: 2 products

OpenShift Service Mesh 2.0
OpenShift Service Mesh 2.1

Timeline

2026-10-02 Threatist record created from CVE-2022-23606

References

Patch 1

https://github.com/envoyproxy/envoy/commit/4b6dd3b53cd5c6d4d4df378a2fc62c1707522b31

Advisory 1

https://github.com/envoyproxy/envoy/security/advisories/GHSA-9vp2-4cp7-vvxf

TI-2026-79288 Out-of-bounds write in Google Brotli decoder KEVCVSS 4.0CRITICAL 9.2
TI-2023-23979 The HTTP/2 protocol allows a denial of service (server resource consumption) because… KEVCVSS 3.1HIGH 7.5
TI-2024-20001 HTTP/2: CPU exhaustion due to CONTINUATION frame flood CVSS 3.1HIGH 7.5
TI-2024-18524 HTTP/2: memory exhaustion due to CONTINUATION frame flood CVSS 3.1HIGH 7.5
TI-2023-12215 Envoy client may fake the header `x-envoy-original-path` CVSS 3.1CRITICAL 9.1
TI-2023-18002 Envoy vulnerable to OAuth2 credentials exploit with permanent validity CVSS 3.1CRITICAL 9.8

See all 126 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences