CVE-2026-77248

Summary

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the streamable HTTP transport accepts requests without a user identity and falls back to operator credentials, while upload_attachment accepts an unrestricted file_path. An unauthenticated network caller can read files available to the MCP process, upload them to an attacker-selected Jira issue or Confluence page, and retrieve the contents. The advisory traces the vulnerable input and processing flow through streamable-http, UserTokenMiddleware, upload_attachment, file_path, and _get_fetcher, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

Affected Software

VendorProductVersion RangeStatus
soopersetmcp-atlassian< 0.22.0affected

Weaknesses

  • CWE-22: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-306: CWE-306: Missing Authentication for Critical Function

References