This vulnerability arises from improper handling of the 'code' argument in the MCP OAuth Local Callback Server endpoint of CherryHQ cherry-studio. Manipulating the argument enables an attacker to bypass normal authorization checks, granting unauthorized access to protected resources and potentially exposing sensitive information or enabling further malicious actions. The weakness is a classic example of improper authorization (CWE-266/CWE-285).

Vulnerable versions are cherry-studio 1.9.6 and earlier. The issue resides in src/main/services/mcp/oauth/callback.ts. Systems running these versions are at risk; newer releases or patched code are not affected.

The vulnerability scores a CVSS of 6.3, reflecting moderately high severity. EPSS data is unavailable, so the current exploitation probability cannot be precisely quantified, but the public disclosure and the existence of a remote attack vector raise concern. No listing in CISA KEV indicates no known large-scale exploit, yet the high complexity and difficulty of exploitation suggest that attacks would require specialized knowledge. Administrators should treat it as a medium threat until an official fix is released.