CVE-2026-77267
MEDIUMCVSS 6.5Description
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the X-Atlassian-Jira-Url and X-Atlassian-Confluence-Url headers are processed by _process_authentication_headers and used to construct Atlassian fetchers without calling validate_url_for_ssrf. A caller who can set these headers can supply an internal or metadata-service URL and cause the server to send requests to that destination, bypassing the incomplete CVE-2026-27826 remediation. This issue is fixed in version 0.22.0.
Timeline
Published:September 22nd, 2026 6:17 PM
Last modified:September 29th, 2026 6:59 PM
CVSS Scoring
CVSS v3: 6.5 (MEDIUM)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Affected Software
From NVD CPE configuration data
Vendors
mcp-atlassian
Products
mcp_atlassian
Weaknesses (CWE)
References & Reports
Advisories, patches, and third-party reports
- https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460Patch
- https://github.com/sooperset/mcp-atlassian/pull/1448Issue Tracking
- https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0Release Notes
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-5wf4-jqxh-8gm3Exploit
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-5wf4-jqxh-8gm3Exploit
Source: NIST NVD · Data may lag official sources by up to one minute