CVEvulnerability

CVE-2026-77246

8.6 HIGH Published 2026-09-22 Modified 2026-09-28 Official page ↗
Status
Analyzed
Published
2026-09-22
Last modified
2026-09-28
Assigner
[email protected]
CVSS 3.1 ([email protected])
7.4 HIGH — CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
CVSS 3.1 ([email protected])
8.6 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
Weaknesses
CWE-200, CWE-22, CWE-441

Description

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, an HTTP transport deployment with READ_ONLY_MODE=false accepts a request without an Authorization identity and permits attacker-controlled Atlassian service headers, including X-Atlassian-Confluence-Url, to select a public attacker hostname or one allowed by MCP_ALLOWED_URL_DOMAINS. A caller can then invoke confluence_upload_attachment or the Jira attachment variant in src/mcp_atlassian/jira/attachments.py with a server-local file_path and cause the MCP process to send the file to the selected attachment endpoint. This issue is fixed in version 0.22.0.

Affected configurations

• mcp-atlassian mcp atlassian (< 0.22.0)

Related

Weakness · CWE (3)

  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor weakness
  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory weakness
  • CWE-441 Unintended Proxy or Intermediary weakness

References