CVSS 3.1
5.5 mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:NCVE-2026-77268
Medium (5.5) in mcp-atlassian mcp atlassian. EPSS 0.2% 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 OAuth fallback token directory and JSON file are created without explicit owner-only modes. Local users or processes with access through the resulting group or world permission bits can read access and refresh tokens and reuse the associated Atlassian session. The advisory traces the vulnerable input and processing flow through ~/.mcp-atlassian, oauth-<client_id>.json, access_token, and refresh_token, which identify the affected entry points, controls, and code paths. This issue is fixed in version 0.22.0.
Severity
- EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 4% of CVEs (scores of 2026-10-31)
- CWE
- CWE-732
- Published
- Modified
- Record from
- the NVD, synced
Affected
- mcp-atlassian:mcp_atlassian
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-4596-2p6p-28cv | PyPI | mcp-atlassian | <0.22.0 | 0.22.0 |
| PYSEC-2026-4082 | PyPI | mcp-atlassian | <0.22.0 | 0.22.0 |