Path Traversal in Sooperset Mcp-Atlassian

CVE-2026-77259

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, confluence_upload_attachment opens a caller-selected server-local file without checking that the resolved path remains in the workspace. A caller can upload environment files, credentials, or other readable host data to a Confluence page and retrieve it through Atlassian. The advisory traces the vulnerable input and processing flow through confluence_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.

Vulnerability class: Path Traversal (Directory Traversal)

Published .

CVSS v3 metric

CVSS v3 base score 7.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-77259?
CVE-2026-77259 is a high-severity vulnerability in Sooperset Mcp-Atlassian, classified under Path Traversal. CVSS score: 7.7/10. Published 2026-09-22.
How severe is CVE-2026-77259?
High severity. CVSS v3 base score is 7.7 out of 10.