A flaw in the fetch function of the AI Proxy Middleware in BigSweetPotatoStudio HyperChat enables an attacker to manipulate the baseurl argument, causing the server to request arbitrary URLs on behalf of the compromised system. This server‑side request forgery can allow access to internal resources, data exfiltration, or further lateral movement, affecting confidentiality and integrity. The vulnerability is classified as CWE‑918 and has a CVSS score of 6.9, indicating moderate severity.

The issue affects BigSweetPotatoStudio HyperChat versions up to and including 2.0.0‑alpha.63. Users running any of these releases should verify their installation and consider upgrading to a fixed version once available.

The exploit is remote and publicly available, though the EPSS score is not reported. The vulnerability has not been listed in the CISA KEV catalog, suggesting no confirmed exploitation in the wild to date. Nevertheless, the moderate CVSS score and the remote launch capability mean that an attacker can potentially leverage this flaw without needing local access, especially if the AI Proxy Middleware is exposed to the Internet.