Vulnerability details
CVE-2026-77253
MCP Atlassian: Jira and Confluence attachment upload tools can read arbitrary server-local files
Official description
MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, Jira and Confluence attachment upload tools accept arbitrary local filesystem paths and send the selected bytes to Atlassian. In HTTP or multi-user deployments, a caller can cross the client-to-server filesystem boundary and disclose configuration, credentials, mounted secrets, or other files readable by the MCP process. The advisory traces the vulnerable input and processing flow through jira_upload_attachment, confluence_upload_attachment, file_path, and server-local filesystem, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.1High | 3.1 | CVEProject cvelistV5 (CNA) (GitHub_M) | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| sooperset | mcp-atlassian | < 0.22.0 | CVEProject cvelistV5 (CNA) |
References and advisories
4- https://github.com/sooperset/mcp-atlassian/pull/1448 x_refsource_MISC
- https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460 x_refsource_MISC
- https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0 x_refsource_MISC
- https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-vc25-24vv-fxxm x_refsource_CONFIRM
Details
- Published
- 2026-09-22
- Last updated
- 2026-09-22
- State
- Published
- Assigner (CNA)
- GitHub_M
Exploit prediction (EPSS)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- Proof of concept
- Technical impact
- Partial
Weaknesses (CWE)
- CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')