CVE-2026-77255
Description
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the Jira update_issue attachments argument is converted into local paths and routed to the attachment upload implementation without workspace validation. A caller can make the MCP server read arbitrary local files and attach them to a Jira issue, using the server as a confused deputy to exfiltrate the contents. The advisory traces the vulnerable input and processing flow through jira update_issue, attachments, upload_attachment, and file_path, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
How to fix
- mcp-atlassian mcp_atlassian0.22.0 or later
- mcp-atlassian0.22.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mcp-atlassian mcp_atlassian | v < 0.22.0 | 0.22.0 |
| mcp-atlassianPyPI | v < 0.22.0 | 0.22.0 |
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Attack Surface Management
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