CVE-2026-77270

Name of the Vulnerable Software and Affected Versions MCP Atlassian versions prior to 0.22.0

Description The Jira and Confluence attachment upload tools fail to validate file paths, allowing for path traversal. An authenticated MCP client or an AI assistant manipulated via prompt injection can provide arbitrary values to the file path variable, which the server treats as trusted local paths. This allows the disclosure and exfiltration of any file readable by the server process, such as environment files, SSH keys, and application configurations, by uploading them to a Confluence page or Jira issue. The issue occurs within the confluence upload attachment and jira upload attachment functions, specifically where open(file path, "rb") is called without using the validate safe path utility.

Recommendations Update MCP Atlassian to version 0.22.0. As a temporary workaround, restrict write access to the MCP server to prevent the use of upload tools until the update is applied.