The vulnerability allows an attacker to send requests to internal resources by setting the x-portkey-custom-host header on the "/v1/proxy/*" endpoint. Authorization headers sent with the forged request can reach protected internal services, allowing exfiltration of provider API keys and potentially other sensitive data. The impact is the compromise of confidentiality and integrity of internal credentials.

Portkey‑AI Gateway versions up to and including 1.15.2 are affected. The vulnerability exists in the gateway’s publicly exposed proxy route, which accepts arbitrary host headers without validation.

The CVSS score of 8.7 indicates a high severity. Because the flaw is a classic SSRF with no listed exploitation in KEV and no EPSS data, the likelihood is uncertain but the high score recommends urgent action. The likely attack vector is an unauthenticated external user sending crafted requests to the vulnerable endpoint. Once exploited, the attacker can access internal services and retrieve API keys.