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1 vulnerability by diillson
CVE-2026-123271 (GCVE-0-2026-123271)
Vulnerability from cvelistv5 – Published: 2026-11-05 18:45 – Updated: 2026-11-09 17:44
VLAI
EPSS
VEX
Title
ChatCLI before v1.215.2 Origin Validation Error via Unvalidated MCP OAuth Resource Indicator
Summary
ChatCLI before v1.215.2 contains an improper validation vulnerability in the MCP OAuth login flow that uses server-supplied Protected Resource Metadata as the resource indicator without checking it matches the configured server URL. A malicious MCP server can declare another resource on the same authorization server, obtain the user's bearer token for it, and replay that token against the other resource.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-09 17:35 UTC
CWE
- CWE-346 - Origin Validation Error
Assigner
VulnCheck
CNA
References
5 references
| URL | Tags |
|---|---|
| https://github.com/diillson/chatcli/security/advi… | vendor-advisory |
| https://github.com/diillson/chatcli/commit/951fe2… | patch |
| https://github.com/diillson/chatcli/releases/tag/… | release-notes |
| https://github.com/diillson/chatcli/blob/359eb27d… | technical-description |
| https://www.vulncheck.com/advisories/chatcli-befo… | third-party-advisory |
Impacted products
Date Public
2026-10-11 00:00
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