# CVE-2026-73497

## Summary

- **CVE ID:** CVE-2026-73497
- **Severity:** MEDIUM
- **CVSS Score:** 6.5 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N)
- **CWE:** CWE-918
- **Published:** Sep 14, 2026
- **Last Modified:** Sep 15, 2026

## Description

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). From 0.17.0 until 0.22.0, validate_url_for_ssrf resolves the attacker-controlled X-Atlassian-Jira-Url and X-Atlassian-Confluence-Url header host once at middleware time, but the outbound request is built with the raw hostname and resolves it again at connection time with no IP pinning. An attacker-controlled DNS-rebinding name can return a public IP during validation and 169.254.169.254 or another internal IP during connection, enabling unauthenticated server-side requests to cloud metadata or internal services. The flaw spans src/mcp_atlassian/utils/urls.py, src/mcp_atlassian/servers/main.py, and src/mcp_atlassian/servers/dependencies.py; validate_url_for_ssrf returns only a verdict rather than a pinned IP, UserTokenMiddleware processes the attacker-controlled headers before fetcher creation, and the Jira and Confluence fetchers use the raw hostname. This issue is fixed in version 0.22.0.

## Affected Products

- sooperset — mcp-atlassian (>= 0.17.0, < 0.22.0)

## References

- [CNA](https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-489g-7rxv-6c8q)
- [CNA](https://github.com/sooperset/mcp-atlassian/pull/1448)
- [CNA](https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460)
- [CNA](https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.23%
- **EPSS Percentile:** 14.2

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-17._