---
cve: "CVE-2022-21657"
severity: "MEDIUM"
cvss: 6.8
epss: "0.5%"
vendor: "envoyproxy"
kev: false
exploited: false
published: "2022-02-22 22:30:12"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-22T21:52:41+02:00"
---

# CVE-2022-21657

> 6.8 MEDIUM · 🧪 PoC

## Beschreibung

Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions Envoy does not restrict the set of certificates it accepts from the peer, either as a TLS client or a TLS server, to only those certificates that contain the necessary extendedKeyUsage (id-kp-serverAuth and id-kp-clientAuth, respectively). This means that a peer may present an e-mail certificate (e.g. id-kp-emailProtection), either as a leaf certificate or as a CA in the chain, and it will be accepted for TLS. This is particularly bad when combined with the issue described in pull request #630, in that it allows a Web PKI CA that is intended only for use with S/MIME, and thus exempted from audit or supervision, to issue TLS certificates that will be accepted by Envoy. As a result Envoy will trust upstream certificates that should not be trusted. There are no known workarounds to this issue. Users are advised to upgrade.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Keine | good |

## Patch verfügbar (OSV)

- a79ca225f1ed924b855dff8a26bd7f7cdb84e694 (Commit)
- a17cdcdfad24de101e95716b77549ba689824f25 (Commit)

## Referenzen

- <https://github.com/envoyproxy/envoy/security/advisories/GHSA-837m-wjrv-vm5g>
- <https://github.com/envoyproxy/envoy/pull/630>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2022-21657) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_