A vulnerability (CVE-2026-102895) was discovered in GPUStack, an open-source software managing GPU clusters, prior to version 2.2.0. The vulnerability allows attackers to bypass authentication and access control by spoofing a custom header, "X-Gpustack-Real-IP", which identifies the request's origin as loopback (127.0.0.1). This causes GPUStack to trust the request and bypass authentication. The vulnerability affects users who rely on GPUStack for AI workloads, as attackers can access sensitive resources, including AI models and messages, without proper authentication.