CVE-2026-77257
Received Received - Intake

Path Traversal in MCP Atlassian Server

Publication date: 2026-09-22

Last updated on: 2026-09-22

Assigner: GitHub, Inc.

Description
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, HTTP-exposed Jira and Confluence upload tools pass a caller-provided file_path to local file operations without restricting it to the workspace. A remote MCP caller with tool access can cause the server to read sensitive local files and upload them as Atlassian attachments. The advisory traces the vulnerable input and processing flow through streamable-http, upload_attachment, and file_path, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

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Meta Information

Published
2026-09-22
Last Modified
2026-09-22
Generated
2026-09-22
AI Q&A
2026-09-22
EPSS Evaluated
N/A
NVD
CVE-2026-77257
EUVD
EUVD-2026-84741

Affected Vendors & Products

Showing 4 associated CPEs
Vendor Product Version / Range
sooperset mcp-atlassian to 0.22.0 (exc)
atlassian confluence to 0.22.0 (exc)
atlassian jira to 0.22.0 (exc)
atlassian mcp 0.22.0

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-22 The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

Attack-Flow Graph

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Executive Summary

CVE-2026-77257 is a vulnerability in MCP Atlassian versions prior to 0.22.0. It allows authenticated remote attackers with tool access to read arbitrary server-local files via HTTP upload tools for Jira or Confluence. The server processes caller-provided file paths without validation, enabling path traversal attacks that expose sensitive files like API tokens or configuration secrets.

Detection Guidance

Check if your mcp-atlassian server is running version 0.22.0 or later. Inspect HTTP logs for unusual file upload requests with suspicious file paths. Look for attachments in Jira or Confluence that reference unexpected local files.

Impact Analysis

An attacker could exploit this to read sensitive files on the server where MCP Atlassian is running. If the server has access to credentials or configuration files, those could be exposed. The attacker needs authenticated tool access but could steal data without direct remote code execution.

Compliance Impact

This vulnerability could lead to unauthorized access to sensitive data, violating GDPR (data protection) and HIPAA (health information privacy). Exposure of personal or health data may result in compliance breaches, legal penalties, and reputational damage.

Mitigation Strategies

Upgrade mcp-atlassian to version 0.22.0 or later immediately. Disable HTTP upload tools if not required. Restrict MCP caller tool access to only necessary functions. Validate all file paths in upload requests against a strict allowlist.

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