CVE-2026-123271

CVE-2026-123271CVE-2026-123271

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.

Scoring

CVSS 8.0 ()
VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N
Last modified2026-11-05
Sourced from NVD. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.