CVE-2026-77270

MCP Atlassian: Arbitrary File Read via Upload Attachment Tools

State
Published
Severity
6.5 Medium
Published
Sep 22, 2026
Updated
Sep 22, 2026
Reserved
Aug 20, 2026

Read the record on cve.org

Description

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the Jira and Confluence attachment upload tools treat caller-controlled file_path values as trusted server-local paths. The server opens the selected file and uploads it to an Atlassian issue or page, allowing an MCP caller with upload access to disclose any file readable by the server process. The advisory traces the vulnerable input and processing flow through confluence_upload_attachment, jira_upload_attachment, file_path, and open(file_path, "rb"), which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

Scores

CVSSScoreVectorSource
3.16.5 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:NGitHub_M

Weaknesses

  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Affected Products

ProductVersions
mcp-atlassiansooperset
  • < 0.22.0Affected

References

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