MCP Atlassian: SSRF Protection Bypass
cve-program · CVE-2026-77274
PublishedMCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, validate_url_for_ssrf has a backslash authority confusion because it interprets the authority differently from the Requests connection layer in the header-based Jira and Confluence URL authentication flow. A crafted URL can validate as an external hostname while the HTTP client connects to an internal host, permitting server-side requests to protected network resources. This issue is fixed in version 0.22.0.
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cve-program · CVE-2026-77274
PublishedMCP Atlassian: SSRF Protection Bypass
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, validate_url_for_ssrf has a backslash authority confusion because it interprets the authority differently from the Requests connection layer in the header-based Jira and Confluence URL authentication flow. A crafted URL can validate as an external hostname while the HTTP client connects to an internal host, permitting server-side requests to protected network resources. This issue is fixed in version 0.22.0.
- Source published
- 22 Sep 2026 17:36:49 UTC
- Source modified
- 22 Sep 2026 18:32:22 UTC
- Saved here
- 23 Oct 2026 15:48:27 UTC
- Source terms
- CVE Program Terms of Use
Original source record · Cite this exact observation · Complete original publisher JSON
Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.
CVSS 4.0 · 8.8 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N