CVE-2026-77271: Mcp-Atlassian Mcp Atlassian

High severity, CVSS 8.8. EPSS: 0.5% chance of exploitation in the next 30 days.

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, validate_safe_path defaults its base directory to os.getcwd(), and affected Confluence attachment call sites omit base_dir, allowing attacker-selected writes within the working directory. This Python module overwrite can provide code execution when the application later imports the modified module, bypassing the remediation tracked as CVE-2026-27825. This issue is fixed in version 0.22.0.

Affected products

• Mcp-Atlassian Mcp Atlassian: before 0.22.0 (fixed in 0.22.0)

Published 2026-09-22. Last modified 2026-09-28.