---
cve: "CVE-2026-77246"
severity: "HIGH"
cvss: 7.4
epss: "0.3%"
vendor: "sooperset"
kev: false
exploited: false
published: "2026-09-22 19:16:48"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-24T11:21:00+02:00"
---

# CVE-2026-77246

> 7.4 HIGH · 🧪 PoC

## Beschreibung

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, an HTTP transport deployment with READ_ONLY_MODE=false accepts a request without an Authorization identity and permits attacker-controlled Atlassian service headers, including X-Atlassian-Confluence-Url, to select a public attacker hostname or one allowed by MCP_ALLOWED_URL_DOMAINS. A caller can then invoke confluence_upload_attachment or the Jira attachment variant in src/mcp_atlassian/jira/attachments.py with a server-local file_path and cause the MCP process to send the file to the selected attachment endpoint. This issue is fixed in version 0.22.0.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- b041733473f95119dd539542a43c280737a8e460 (Commit)

## Referenzen

- <https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-wv8v-v4c5-v75j>
- <https://github.com/sooperset/mcp-atlassian/pull/1448>
- <https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460>
- <https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-77246) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_