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CVE-2026-71424 (GCVE-0-2026-71424)

Vulnerability from cvelistv5 – Published: 2026-08-17 21:28 – Updated: 2026-08-18 17:47
VLAI
Title
Onyx: Cross-user OAuth-token leak via /api/mcp/servers* for per-user MCP servers
Summary
Onyx is an open-source AI platform. Prior to 3.1.10, 3.2.14, and 4.0.0, Onyx's GET /api/mcp/servers and GET /api/mcp/servers/persona/{persona_id} endpoints expose another user's OAuth Authorization header because OnyxTokenStorage.set_tokens and OnyxTokenStorage.set_client_info in backend/onyx/server/features/mcp/api.py copy per-user tokens into a shared admin MCPConnectionConfig row and _db_mcp_server_to_api_mcp_server returns that row through auth_template.headers to any BASIC_ACCESS user. This issue is fixed in versions 3.1.10, 3.2.14, and 4.0.0.
Severity
9.6 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-18 17:28 UTC
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-863 - Incorrect Authorization
Assigner
References
Impacted products
Vendor Product Version CPE status
onyx-dot-app onyx Affected: < 3.1.10
Affected: >= 3.2.0, < 3.2.14
Affected: >= 3.3.0-beta.0, < 4.0.0
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