MCP Atlassian vulnerabilities

In MCP Atlassian from 0.17.0 until 0.22.0, validate_url_for_ssrf resolves the attacker-controlled X-Atlassian-Jira-Url and X-Atlassian-Confluence-Url header host once at middleware time, but the outbound request uses the raw hostname and resolves it again without IP pinning. This enables DNS-rebinding attacks and unauthenticated requests to cloud metadata or internal services.

MCP Atlassian before 0.22.0 allows a client with write-tool access to pass file paths without confinement to the server, leading to disclosure of server files, Atlassian credentials, or another tenant's data.

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, confluence_upload_attachment passes its client-supplied file_path directly to open(file_path, "rb") in src/mcp_atlassian/confluence/attachments.py through _upload_attachment_direct() without calling validate_safe_path. An authenticated MCP client can read any file accessible to the server process and exfiltrate it to Confluence as an attachment. If an AI agent can be induced to call the tool through untrusted content, the same flaw can disclose server environment variables such as CONFLUENCE_API_TOKEN and other credentials. This issue is fixed in version 0.22.0.