---
cve: "CVE-2026-63306"
severity: "CRITICAL"
cvss: 9.2
epss: "0.4%"
vendor: "stoatchat"
kev: false
exploited: false
published: "2026-07-16 13:16:33"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-10-02T00:47:38+02:00"
---

# CVE-2026-63306

> 9.2 CRITICAL · 🧪 PoC

## Beschreibung

stoatchat before 0.13.5 contains an unauthenticated server-side request forgery vulnerability in the /proxy and /embed endpoints that accept arbitrary URLs without DNS resolution filtering or private IP range validation. Attackers can enumerate internal services, fingerprint applications, and reach instance metadata endpoints by supplying malicious URLs or leveraging redirect chains to access internal infrastructure.

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **poc**
  - Automatable: **yes**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 6c920de03a275e73f1f632b6cd6bc924acb66324 (Commit)

## Referenzen

- <https://github.com/stoatchat/stoatchat/security/advisories/GHSA-xhww-5g9p-vvq5>
- <https://www.vulncheck.com/advisories/stoatchat-before-unauthenticated-ssrf-via-proxy-and-embed-endpoints>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-63306) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_