CVE-2026-123271

HighCVSS 8.0/10Last modified Nov 12, 2026

Description

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.

Metrics

CVSS 3.1 8.0/10CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N

Weakness enumeration

CWE-346

Affected software

No affected versions have been published.

Timeline

Published: Nov 5, 2026
Last modified: Nov 12, 2026
NVD status: Deferred

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