1MCP Agent (@1mcp/agent) 0.20.0 through 0.39.0 contains an incorrect authorization vulnerability that allows authenticated clients to bypass OAuth tag-scope enforcement using negated advanced tag-filter expressions. Attackers holding a single-tag token can send a filter like not <granted-tag> to list and invoke tools on backend MCP servers outside their granted scopes.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Sat, 10 Oct 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 1MCP Agent (@1mcp/agent) 0.20.0 through 0.39.0 contains an incorrect authorization vulnerability that allows authenticated clients to bypass OAuth tag-scope enforcement using negated advanced tag-filter expressions. Attackers holding a single-tag token can send a filter like not <granted-tag> to list and invoke tools on backend MCP servers outside their granted scopes. | |
| Title | 1MCP Agent 0.20.0 through 0.39.0 OAuth Tag-Scope Bypass via Negated Tag Filter | |
| Weaknesses | CWE-863 | |
| References |
|
|
| Metrics |
cvssV3_1
|
Projects
Sign in to view the affected projects.
Status: PUBLISHED
Assigner: VulnCheck
Published:
Updated: 2026-10-10T16:14:10.297Z
Reserved: 2026-10-10T16:07:40.380Z
Link: CVE-2026-108586
No data.
Status : Received
Published: 2026-10-10T17:17:00.593
Modified: 2026-10-10T17:17:00.593
Link: CVE-2026-108586
No data.
OpenCVE Enrichment
Updated: 2026-10-10T17:30:05Z
Weaknesses