CVE-2026-77249

medium

MCP 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, 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.

CVSS

5.3

5.3 (CVSS v3.1)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Severity source: NVD CVSS v3.1 (security-advisories@github.com)

Timeline (UTC)

Published: 2026-09-22 19:16

Modified: 2026-09-29 18:59

NVD status: Analyzed

Last synced 2 days ago

Verified against the source API 2026-10-27 06:55 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

mcp-atlassian / mcp_atlassian <0.22.0

Weakness classification (CWE)

CWE-918

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-v9m3-wfh8-5646

Patch / mitigation: https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460

Patch / mitigation: https://github.com/sooperset/mcp-atlassian/pull/1448

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-v9m3-wfh8-5646 security-advisories@github.com

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 06:55 UTC · record ↗

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CVE-2026-77249

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