CVE-2026-77253CWE-22path-traversal

CVE-2026-77253

High · published September 22, 2026

CVSS v3.1
7.1
EPSS
0%
Percentile
30.1
In the wild
Unconfirmed
What it is

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, Jira and Confluence attachment upload tools accept arbitrary local filesystem paths and send the selected bytes to Atlassian. In HTTP or multi-user deployments, a caller can cross the client-to-server filesystem boundary and disclose configuration, credentials, mounted secrets, or other files readable by the MCP process. The advisory traces the vulnerable input and processing flow through jira_upload_attachment, confluence_upload_attachment, file_path, and server-local filesystem, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

The record
Technical detail
CVSS v3.1
7.1 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00373 · 30.1th percentile
Weakness
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Published
2026-09-22T23:16Z
Affected products (1)
ProductVersionsFixed in
mcp-atlassian/mcp_atlassian< 0.22.00.22.0
References (5)
EPSS history
Timeline
  • 24 SEP 03:25Z
    EPSS moved — → 0%
    epss
  • 22 SEP 18:10Z
    MCP Atlassian: Jira and Confluence attachment upload tools can read arbitrary server-local files
    cvelistv5