Medium severity6.5NVD Advisory· Published Sep 22, 2026· Updated Sep 29, 2026
CVE-2026-77267
CVE-2026-77267
Description
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
mcp-atlassianPyPI | < 0.22.0 | 0.22.0 |
Affected products
3cpe:2.3:a:mcp-atlassian:mcp_atlassian:*:*:*:*:*:*:*:*+ 1 more
- cpe:2.3:a:mcp-atlassian:mcp_atlassian:*:*:*:*:*:*:*:*range: <0.22.0
- (no CPE)range: <0.22.0
- Range: <0.22.0
Patches
Vulnerability mechanics
References
6- github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460nvdPatchWEB
- github.com/sooperset/mcp-atlassian/pull/1448nvdIssue TrackingPatchWEB
- github.com/sooperset/mcp-atlassian/security/advisories/GHSA-5wf4-jqxh-8gm3nvdExploitVendor AdvisoryWEB
- github.com/advisories/GHSA-5wf4-jqxh-8gm3ghsaADVISORY
- nvd.nist.gov/vuln/detail/CVE-2026-77267ghsaADVISORY
- github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0nvdRelease NotesWEB
News mentions
1- Atlassian MCP: 25 Coordinated Vulnerabilities Expose Jira, Confluence IntegrationsVypr Intelligence · Sep 22, 2026