CVE-2026-77270

## 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 validate_safe_path function is imported (line 9) but never called in the upload path. ### Jira: src/mcp_atlassian/jira/attachments.py:353-415 # src/mcp_atlassian/jira/attachments.py:373-379 # 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 same pattern: validate_safe_path is imported (line 10) but never called in upload_attachment. T