CVE-2026-77270
Published:September 22, 2026
Updated:September 23, 2026
MCP 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.
Affected Packages
mcp-atlassian (CONDA):
Affected version(s) =0.21.1 <0.22.0Fix Suggestion:
Update to version 0.22.0https://github.com/sooperset/mcp-atlassian.git (GITHUB):
Affected version(s) >=v0.5.0 <v0.22.0Fix Suggestion:
Update to version v0.22.0mcp-atlassian (PYTHON):
Affected version(s) >=0.1.0 <0.22.0Fix Suggestion:
Update to version 0.22.0Related Resources (6)
Do you need more information?
Contact UsCVSS v4
Base Score:
7.1
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
6.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')