CVSS 4.0
8.3 highCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:NCVE-2026-77267
High (8.3) in mcp-atlassian mcp atlassian. EPSS 0.3% chance of exploitation in the next 30 days. Fixed in mcp-atlassian 0.22.0.
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the X-Atlassian-Jira-Url and X-Atlassian-Confluence-Url headers are processed by _process_authentication_headers and used to construct Atlassian fetchers without calling validate_url_for_ssrf. A caller who can set these headers can supply an internal or metadata-service URL and cause the server to send requests to that destination, bypassing the incomplete CVE-2026-27826 remediation. This issue is fixed in version 0.22.0.
Severity
CVSS 3.1
6.5 mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N- EPSS
- 0.3% chance of exploitation in the next 30 days; higher than 25% of CVEs (scores of 2026-10-31)
- CWE
- CWE-918
- Published
- Modified
- Record from
- the NVD, synced
Affected
- mcp-atlassian:mcp_atlassian
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-5wf4-jqxh-8gm3 | PyPI | mcp-atlassian | <0.22.0 | 0.22.0 |
| PYSEC-2026-4084 | PyPI | mcp-atlassian | <0.22.0 | 0.22.0 |
References
- 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
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-5wf4-jqxh-8gm3
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-5wf4-jqxh-8gm3