CVE-2026-77259CWE-22CWE-552path-traversal

CVE-2026-77259

High · published September 22, 2026

CVSS v3.1
7.7
EPSS
0%
Percentile
33.9
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, 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.

The record
Technical detail
CVSS v3.1
7.7 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00408 · 33.9th percentile
Weaknesses
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'); CWE-552 · Files or Directories Accessible to External Parties
Published
2026-09-22T23:16Z
Affected products (1)
ProductVersionsFixed in
mcp-atlassian/mcp_atlassian< 0.22.00.22.0
References (5)
https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460 · [email protected]https://github.com/sooperset/mcp-atlassian/pull/1448 · [email protected]https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0 · [email protected]https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-6cr4-ccf3-x7h4 · [email protected]https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-6cr4-ccf3-x7h4 · 134c704f-9b21-4f2e-91b3-4a467353bcc0
EPSS history
Timeline
  • 24 SEP 03:25Z
    EPSS moved — → 0%
    epss
  • 22 SEP 18:45Z
    MCP Atlassian: Arbitrary file read via confluence_upload_attachment allows exfiltration of server credentials
    cvelistv5