6.1

CVE-2026-77250

Exploit

MCP Atlassian: OAuth fallback token storage writes plaintext access and refresh tokens with group-readable permissions

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.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Mcp-atlassian ≫ Mcp Atlassian Version < 0.22.0
VulnDex Vulnerability Enrichment
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Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.12% 0.015
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 6.1 1.8 4.2
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
CWE-312 Cleartext Storage of Sensitive Information

The product stores sensitive information in cleartext within a resource that might be accessible to another control sphere.

https://github.com/sooperset/mcp-atlassian/pull/1448
Patch
Issue Tracking
https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460
Patch
https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0
Release Notes
https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-g5xv-mhgm-v5f6
Vendor Advisory
Exploit