https://vulnerability.circl.lu/rss/recent/all/10 Most recent entries from all 2026-10-01T15:51:41.896219+00:00 Vulnerability-Lookup info@circl.lu python-feedgen Contains only the most 10 recent entries. https://vulnerability.circl.lu/vuln/fkie_cve-2026-77270 fkie_cve-2026-77270 2026-10-01T15:51:41.899122+00:00

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.

 https://vulnerability.circl.lu/vuln/ghsa-f26r-j276-ggg4 GHSA-f26r-j276-ggg4 — MCP Atlassian: Arbitrary File Read via Upload Attachment Tools 2026-10-01T15:51:41.899198+00:00

Affected: PyPI: mcp-atlassian

## Summary

The upload attachment tools in both Confluence and Jira accept arbitrary file paths without path traversal validation. The upload_attachment methods read any file accessible to the server process and upload it to a Confluence page or Jira issue. Despite the existence of a validate_safe_path utility function (used correctly in download operations), the upload paths do not use it. This allows an authenticated MCP client (or an AI assistant manipulated via prompt injection) to exfiltrate arbitrary files from the server filesystem to an attacker-controlled Confluence page or Jira issue.

## Details

The vulnerability exists in two parallel code paths:

### Confluence: src/mcp_atlassian/confluence/attachments.py:35-108

# src/mcp_atlassian/confluence/attachments.py:62-65 # Convert to absolute path if relative if not os.path.isabs(file_path): file_path = os.path.abspath(file_path)

# Check if file exists if not os.path.exists(file_path): # error...

The file_path parameter is only checked for existence, not for path traversal. Any path like /etc/passwd, /etc/shadow, ~/.ssh/id_rsa, or ../../../sensitive-file is accepted.

**Contrast with Confluence download operations (which ARE protected):**

# src/mcp_atlassian/confluence/attachments.py:223 validate_safe_path(target_path) # <-- used for downloads

# src/mcp_atlassian/confluence/attachments.py:272 validate_safe_path(target_dir) # <-- used for downloads

The validat…