CVE-2026-77261

EUVD-2026-84631 · Published Sep 22, 2026

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, _make_ssrf_safe_hook is omitted from JiraFetcher and ConfluenceFetcher sessions created through the basic-auth and oauth_pat branches. If an attacker-controlled or compromised configured Atlassian instance returns a redirect to an internal address, those sessions can follow the redirect without revalidating its destination. This issue is fixed in version 0.22.0.

Technologies

Mcp-Atlassian Mcp Atlassian

Weaknesses

CWE-918

CVSS scores

v3.18.5CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N

MITRE ATT&CK

Inferred

Where this vulnerability fits in an attack

ReconImpact

Initial Access

T1190Exploit Public-Facing Application

References

https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-6529-c226-h328
https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460
https://github.com/sooperset/mcp-atlassian/pull/1448
https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0

Potentially impacted assets

See if this affects your attack surface