CVE-2026-77242
highMCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira).
Vendor / product: Mcp-atlassian — mcp atlassian
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, validate_url_for_ssrf checks a hostname's resolved addresses, but Requests and urllib3 resolve the hostname again when connecting. A caller can use a short-lived DNS answer that is public during validation and private during connection, preserving unauthenticated access to internal or metadata endpoints despite the earlier CVE-2026-27826 remediation. The advisory traces the vulnerable input and processing flow through validate_url_for_ssrf, _check_dns_resolution, socket.getaddrinfo, and _make_ssrf_safe_hook, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N Affected products
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
References
- https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460 security-advisories@github.com
- https://github.com/sooperset/mcp-atlassian/pull/1448 security-advisories@github.com
- https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0 security-advisories@github.com
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-72fm-whvq-jghf security-advisories@github.com
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-72fm-whvq-jghf 134c704f-9b21-4f2e-91b3-4a467353bcc0