What is CVE-2026-77249?

CVE-2026-77249 is a medium-severity vulnerability in Sooperset Mcp-Atlassian, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.3/10. Published 2026-09-22.

How severe is CVE-2026-77249?

Medium severity. CVSS v3 base score is 5.3 out of 10.

SSRF in Sooperset Mcp-Atlassian

CVE-2026-77249

MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, JiraUserMixin._lookup_user_by_permissions uses the module-level requests.get function instead of the fetcher's protected session. A caller-controlled public Jira URL can redirect that unhooked request to an internal address, bypassing the redirect checks added for CVE-2026-27826. The advisory traces the vulnerable input and processing flow through JiraUserMixin._lookup_user_by_permissions, requests.get, self.jira._session.get, and _make_ssrf_safe_hook, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.

Vulnerability class: SSRF (Server-Side Request Forgery)

Published 2026-09-22 · last modified 2026-09-22.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Sooperset Mcp-Atlassian — versions < 0.22.0

Weakness classification (CWE)

CWE-918 — Server-Side Request Forgery (SSRF)

References

Frequently asked questions

What is CVE-2026-77249?: CVE-2026-77249 is a medium-severity vulnerability in Sooperset Mcp-Atlassian, classified under Server-Side Request Forgery (SSRF). CVSS score: 5.3/10. Published 2026-09-22.
How severe is CVE-2026-77249?: Medium severity. CVSS v3 base score is 5.3 out of 10.