23 Oct 2026 15:48:27 UTC
MCP Atlassian: Arbitrary File Read via Upload Attachment Tools
cve-program · CVE-2026-77270 · Published
CVE-2026-77270
MCP Atlassian: Arbitrary File Read via Upload Attachment Tools
CVSS 3.1 6.5 MEDIUMCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-77270
PublishedMCP 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.
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