What is the CVSS score of CVE-2026-27825?

CVE-2026-27825 has a CVSS 3.1 base score of 9.0 (Critical). CVSS vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. EPSS exploitation probability: 0.0%.

Which versions of Atlassian are affected by CVE-2026-27825?

A critical path traversal vulnerability in MCP Atlassian (CVE-2026-27825) allows attackers to write files outside intended directories, potentially enabling arbitrary file placement and system…. A patch is available.

How to fix or mitigate CVE-2026-27825?

Within 24 hours: Inventory all systems running MCP Atlassian and confirm versions prior to 0.17.0; disable the confluence_download_attachment tool if possible or restrict network access to the MCP server. Within 7 days: Implement network segmentation to limit MCP server communications; deploy WAF rules to block suspicious download_path parameters; conduct audit of recent file writes to detect exploitation. Within 30 days: Upgrade MCP Atlassian to version 0.17.0 or later once available; review access logs for indicators of compromise; validate system file integrity.

Atlassian CVE-2026-27825

CRITICAL

Path Traversal (CWE-22)

2026-03-10 security-advisories@github.com

GHSA-xjgw-4wvw-rgm4

Atlassian Path Traversal RCE

9.0

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

9.0 CRITICAL

AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Patch released

Mar 31, 2026 - 21:13 nvd

Patch available

Analysis Generated

Mar 12, 2026 - 21:55 vuln.today

CVE Published

Mar 10, 2026 - 20:16 nvd

CRITICAL 9.0

DescriptionGitHub Advisory

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to version 0.17.0, the confluence_download_attachment MCP tool accepts a download_path parameter that is written to without any directory boundary enforcement. An attacker who can call this tool and supply or access a Confluence attachment with malicious content can write arbitrary content to any path the server process has write access to. Because the attacker controls both the write destination and the written content (via an uploaded Confluence attachment), this constitutes for arbitrary code execution (for example, writing a valid cron entry to /etc/cron.d/ achieves code execution within one scheduler cycle with no server restart required). Version 0.17.0 fixes the issue.