# CVE-2022-23606: Crash when a cluster is deleted in Envoy

> An attacker can crash the Envoy proxy by triggering infinite recursion during cluster deletion with many idle connections, causing denial of service.

- **Severity:** Medium 4.4 (`CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 22 Feb 2022
- **Updated:** 23 Apr 2025
- **Also known as:** BIT-envoy-2022-23606, GHSA-9vp2-4cp7-vvxf

## What is CVE-2022-23606?

CVE-2022-23606 is a medium-severity denial of service vulnerability in Envoyproxy Envoy, published on 22 Feb 2022. An attacker needs administrator access to exploit it, with no action from the victim.

### Official 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.

Weakness: CWE-674 (Uncontrolled Recursion)

## Which versions are affected by CVE-2022-23606?

1 open source package ship an affected version, including envoy. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `envoy` | Bitnami | From 1.20.0 | 1.20.2, 1.21.1 |

Products: Envoyproxy Envoy.

## How do I fix CVE-2022-23606?

Upgrade envoy to a fixed version for your release line: 1.20.2 or 1.21.1.

## Is CVE-2022-23606 being exploited?

There is no known exploitation of CVE-2022-23606 in the wild and no public exploit code.

## Other vulnerabilities in Envoyproxy Envoy

- [CVE-2022-29226](https://insights.sbomify.com/CVE-2022-29226/): Trivial authentication bypass in Envoy (critical 10.0)
- [CVE-2019-18801](https://insights.sbomify.com/CVE-2019-18801/): Memory corruption in n/a (critical 9.8)
- [CVE-2019-18802](https://insights.sbomify.com/CVE-2019-18802/): Security feature bypass in n/a (critical 9.8)
- [CVE-2020-35470](https://insights.sbomify.com/CVE-2020-35470/): Information disclosure in n/a (high 8.8)
- [CVE-2024-23324](https://insights.sbomify.com/CVE-2024-23324/): Envoy ext auth can be bypassed when Proxy protocol filter sets invalid UTF-8 metadata (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-23606 and fix it if it is affected.

What it is: CVE-2022-23606 is a medium-severity denial of service vulnerability in Envoyproxy Envoy, published on 22 Feb 2022. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-23606 in the wild and no public exploit code.

Affected packages and fixed versions:
- envoy (Bitnami): affected from 1.20.0; fixed in 1.20.2, 1.21.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2022-23606/ (Markdown: https://insights.sbomify.com/CVE-2022-23606/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-23606
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-23606
- OSV: https://osv.dev/vulnerability/CVE-2022-23606

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-23606/
Summaries are generated and may contain mistakes; the official description above is the record.