Audits find critical cross-tenant RCE flaws across GPU neocloud providers

Security researchers at SemiAnalysis and ClusterMax audited multiple GPU-as-a-service neocloud providers and found widespread critical vulnerabilities spanning tenant isolation, container security, and credential exposure. One audited environment ran Docker Engine 29.1.3, within the affected range for CVE-2026-41567, which allows malicious containers to execute arbitrary code as root on the host. Researchers documented a full remote code execution chain via a gem exploit, followed by kernel-level privilege escalation using a technique called 'pte_physroot' and CVE-2026-46300, a Linux kernel vulnerability published May 23. ClusterMax researchers found a cross-tenant RCE at an Asian provider where writing to logs in one tenant allowed reading from another, potentially exposing credentials of OpenRouter inference customers. A Grafana dashboard at one provider used a single OAuth token scoped across all tenants, leaking every tenant's metrics to any querying user. Additional findings include exposed cockpit servers potentially vulnerable to CVE-2026-4631, open BMC controllers, missing InfiniBand keys, broken storage isolation, and single-layer container isolation without VM backing. At least one provider was notified and was working with auditors to verify patches at the time of disclosure.