CVSS 3.1
8.6 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:NCVE-2026-77248
High (8.6) in mcp-atlassian mcp atlassian. EPSS 0.5% 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 streamable HTTP transport accepts requests without a user identity and falls back to operator credentials, while upload_attachment accepts an unrestricted file_path. An unauthenticated network caller can read files available to the MCP process, upload them to an attacker-selected Jira issue or Confluence page, and retrieve the contents. The advisory traces the vulnerable input and processing flow through streamable-http, UserTokenMiddleware, upload_attachment, file_path, and _get_fetcher, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
Severity
- EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 41% of CVEs (scores of 2026-10-31)
- CWEs
- CWE-22, CWE-306
- Published
- Modified
- Record from
- the NVD, synced
Affected
- mcp-atlassian:mcp_atlassian
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-cc5h-2pwp-pvcc | PyPI | mcp-atlassian | <0.22.0 | 0.22.0 |
| PYSEC-2026-4089 | 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-cc5h-2pwp-pvcc
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-cc5h-2pwp-pvcc