MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, OAuthConfig writes a plaintext fallback file containing access and refresh tokens under the user's .mcp-atlassian directory using process-default permissions. On systems with a permissive umask, same-group or other local users and processes can read the persisted tokens and reuse the associated Atlassian access. The advisory traces the vulnerable input and processing flow through OAuthConfig._save_tokens, ~/.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.
Metrics
Affected Vendors & Products
References
History
Tue, 29 Sep 2026 14:30:00 +0000
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Mcp-atlassian
Mcp-atlassian mcp Atlassian |
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| CPEs | cpe:2.3:a:mcp-atlassian:mcp_atlassian:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Mcp-atlassian
Mcp-atlassian mcp Atlassian |
Tue, 22 Sep 2026 20:15:00 +0000
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Sooperset
Sooperset mcp-atlassian |
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| Vendors & Products |
Sooperset
Sooperset mcp-atlassian |
Tue, 22 Sep 2026 19:30:00 +0000
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ssvc
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Tue, 22 Sep 2026 18:00:00 +0000
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| Description | MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, OAuthConfig writes a plaintext fallback file containing access and refresh tokens under the user's .mcp-atlassian directory using process-default permissions. On systems with a permissive umask, same-group or other local users and processes can read the persisted tokens and reuse the associated Atlassian access. The advisory traces the vulnerable input and processing flow through OAuthConfig._save_tokens, ~/.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. | |
| Title | MCP Atlassian: OAuth fallback token storage writes plaintext access and refresh tokens with group-readable permissions | |
| Weaknesses | CWE-312 | |
| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-09-22T17:51:02.674Z
Updated: 2026-09-22T18:42:59.068Z
Reserved: 2026-08-20T19:02:23.416Z
Link: CVE-2026-77250
Updated: 2026-09-22T18:42:47.863Z
Status : Analyzed
Published: 2026-09-22T18:17:17.720
Modified: 2026-09-29T14:22:55.913
Link: CVE-2026-77250
No data.