Tools AI Risk Radar ai-incident-0204
Incident record
1MCP tag filters can bypass OAuth tool restrictions
- Severity
- Medium
- Status
- Research
- Type
- Infra Vuln
- Target
- 1MCP Agent 0.20.0 through 0.39.0
- Actor
- researcher
- CVE
- CVE-2026-108586
What happened
A valid OAuth token restricted to one tag can use a negated tag filter to list and invoke tools on MCP servers outside that tag’s scope.
The CVE was published on 10 October; the original researcher publication date is unconfirmed. The deployment must use tag-based authorisation and configure backends outside the caller’s granted tags. The CNA gives CVSS 3.1 score 5.4. Patch status remains unconfirmed as of 11 October.
Sources
- CVE recordcveawg.mitre.org/api/cve/CVE-2026-108586
- Researcher disclosurehackmd.io/@haind/1mcp-negated-tag-filter-oauth-scope-bypass
One record from the AI Risk Radar, maintained by the Security Desk.Data: CSV · JSON ·RSS · CC BY 4.0 with attribution to YFarmX.Tracker updated · 13 October 2026