CVE-2025-22225

VMware ESXi contains an arbitrary write vulnerability (CWE-787/CWE-123) in which an actor with privileges inside the VMX process can trigger a write into the kernel, escaping the ESXi sandbox. The flaw is exploited locally (AV:L), requires high privileges within the VMX process (PR:H), and involves no user interaction, so it is typically reached by chaining another ESXi/VMX bug or after an attacker already has a foothold on the host. Successful exploitation yields a sandbox escape with high confidentiality, integrity, and availability impact, effectively giving the attacker broad control at the hypervisor level. Any organization running VMware ESXi — including the ESXi components within VMware Cloud Foundation and VMware Telco Cloud Infrastructure/Platform — is potentially affected. The flaw is being exploited in the wild and was added to CISA's KEV on 2025-03-04 with known ransomware use; media reports attribute exploitation to China-linked actors, and Broadcom has released urgent patches.

What to do: Apply the ESXi updates released by Broadcom/VMware for CVE-2025-22225 (covering ESXi components inside VMware Cloud Foundation and Telco Cloud deployments), prioritizing internet-facing hosts, and follow CISA KEV required actions — federal agencies must remediate per BOD 22-01 deadlines. Since exploitation is confirmed in the wild with known ransomware use, check ESXi hosts for signs of compromise and restrict/remove management interfaces from the internet until patched. No public PoC is known, so rely on vendor guidance for mitigations if immediate patching is not possible.