GHSA-WM45-QH3G-V83F: GHSA-WM45-QH3G-V83F: Arbitrary Server-Side File Read and Exfiltration via Attachment Upload in mcp-atlassian

#security #cve #cybersecurity #ghsa

GHSA-WM45-QH3G-V83F: Arbitrary Server-Side File Read and Exfiltration via Attachment Upload in mcp-atlassian

Vulnerability ID: GHSA-WM45-QH3G-V83F
CVSS Score: 7.7
Published: 2026-07-10

An arbitrary server-side file read vulnerability exists in the mcp-atlassian integration server. Remote clients utilizing SSE or HTTP transports can exploit the lack of directory containment on attachment-upload tools to resolve and read arbitrary host files, exfiltrating them directly to Atlassian Jira or Confluence.

TL;DR

Remote clients can read and exfiltrate arbitrary files from the host server (such as system configurations and API keys) by exploiting a directory traversal vulnerability in mcp-atlassian before 0.22.0.

⚠️ Exploit Status: POC

Technical Details

CWE ID: CWE-22
Attack Vector: Network
CVSS v3.1: 7.7 (High)
Impact: Arbitrary File Read / Data Exfiltration
Exploit Status: PoC Available
CISA KEV Status: Not Listed

Affected Systems

mcp-atlassian PyPI package deployed over remote network transports (HTTP/SSE)
mcp-atlassian: < 0.22.0 (Fixed in: 0.22.0)

Mitigation Strategies

Upgrade to mcp-atlassian version 0.22.0 or later
Restrict the MCP server's network bindings to 127.0.0.1
Run the MCP server in a containerized environment with a non-root user and minimal read privileges

Remediation Steps:

Identify deployments running mcp-atlassian versions prior to 0.22.0
Update the PyPI dependency to mcp-atlassian>=0.22.0 in requirements.txt or pyproject.toml
Rebuild and redeploy the MCP server container or service
Audit Atlassian Confluence page attachments and Jira ticket attachments for unauthorized files (e.g., passwd, hosts, environ)

Read the full report for GHSA-WM45-QH3G-V83F on our website for more details including interactive diagrams and full exploit analysis.