CVE-2026-77269: mcp-atlassian Path Traversal Vulnerability Allows Arbitrary File Read
Summary
CVE-2026-77269: The confluence_upload_attachment and confluence_upload_attachments MCP tools accept a file_path parameter and do not validate that the path is confined to an allowed directory before opening the file. Affects mcp-atlassian versions < 0.22.0. Fixed in 0.22.0. How to fix ↓
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Background
The mcp-atlassian package is a toolset designed for integrating with Atlassian products, such as Confluence and Jira, allowing users to manage attachments and other resources programmatically. This package facilitates operations like uploading and downloading files, but it has been found to have a critical vulnerability that allows unauthorized file access on the server.
Vulnerability Detail
The vulnerability arises from the lack of validation on the 'file_path' parameter in the 'confluence_upload_attachment' and 'confluence_upload_attachments' MCP tools. This oversight permits an attacker to specify any file path, leading to arbitrary file reads from the server's filesystem. The issue is compounded by the fact that this is an incomplete fix for a previous vulnerability (CVE-2026-27825), where protections were only applied to download operations, leaving upload operations exposed. The potential ramifications include the exfiltration of sensitive files such as SSH keys, API credentials, and configuration files, posing a significant security risk.
How To Fix
Latest published version: 0.23.1 as of 23 Oct 2026
pip install --upgrade "mcp-atlassian==0.23.1"Upgrading to it may include breaking changes; the version below is the minimum fixed release for this vulnerability.
If you need the minimum change
0.22.0
This is the first release that contains the fix.
pip install --upgrade "mcp-atlassian==0.22.0"Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
Currently, there are no specific workarounds mentioned to mitigate this vulnerability without applying the patch. However, restricting access to the MCP tools and monitoring file uploads can help reduce the risk until the patch is applied.
Conclusion
The mcp-atlassian package has a critical vulnerability (CVE-2026-77269) that allows for arbitrary file reads due to inadequate validation of file paths during upload operations. It is crucial to update to the patched version to safeguard against potential data breaches.
See every vulnerability recorded for mcp-atlassian →
FAQ
CVE-2026-77269 is a vulnerability in the mcp-atlassian package that allows attackers to read arbitrary files from the server due to a lack of path validation in file upload operations.
You can check if your application is affected by using the Vulert playground at Vulert Scanner, which monitors open-source vulnerabilities without requiring signup.
The vulnerability can lead to unauthorized access to sensitive files, including SSH keys, API credentials, and configuration files, which can compromise the security of your application.
To fix this vulnerability, update the mcp-atlassian package to version 0.22.0 or later using the command 'pip install --upgrade mcp-atlassian'.
While there are no specific workarounds, limiting access to the MCP tools and monitoring file uploads can help reduce the risk until the patch is applied.
References
Related vulnerabilities
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