Vulnerability Description
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to version 0.17.0, the `confluence_download_attachment` MCP tool accepts a `download_path` parameter that is written to without any directory boundary enforcement. An attacker who can call this tool and supply or access a Confluence attachment with malicious content can write arbitrary content to any path the server process has write access to. Because the attacker controls both the write destination and the written content (via an uploaded Confluence attachment), this constitutes for arbitrary code execution (for example, writing a valid cron entry to `/etc/cron.d/` achieves code execution within one scheduler cycle with no server restart required). Version 0.17.0 fixes the issue.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mcp-Atlassian | Mcp Atlassian | < 0.17.0 |
Related Weaknesses (CWE)
References
- https://github.com/sooperset/mcp-atlassian/commit/52b9b0997681e87244b20d58034deaPatch
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-xjgw-4wvw-rgVendor Advisory
FAQ
What is CVE-2026-27825?
CVE-2026-27825 is a vulnerability with a CVSS score of 9.0 (CRITICAL). MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to version 0.17.0, the `confluence_download_attachment` MCP tool accepts a `download_path` pa...
How severe is CVE-2026-27825?
CVE-2026-27825 has been rated CRITICAL with a CVSS base score of 9.0/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-27825?
Check the references section above for vendor advisories and patch information. Affected products include: Mcp-Atlassian Mcp Atlassian.