CVE-2026-77262

Name of the Vulnerable Software and Affected Versions MCP Atlassian versions 0.17.0 through 0.21.0

Description A path traversal issue exists in the confluence upload attachment tool. The file path variable is passed directly to the open() function without proper validation, allowing a caller to read arbitrary files accessible by the server process. These files can then be exfiltrated by uploading them to an attacker-controlled Confluence host. In default streamable-http transport deployments, the server binds to 0.0.0.0 without authentication, which may allow remote exploitation. This issue is a read-side counterpart to a previous arbitrary file write flaw.

Recommendations Update to version 0.22.0. As a temporary mitigation, restrict the use of the confluence upload attachment tool or ensure the server is not exposed to untrusted networks.