CVE-2025-22225 VMware ESXi Arbitrary Write Vulnerability
VMware ESXi contains an arbitrary write vulnerability. Successful exploitation allows an attacker with privileges within the VMX process to trigger an arbitrary kernel write leading to an escape of the sandbox.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 4 Mar 2025.
- CISA lists it as known to be used in ransomware campaigns.
- Rated High severity (CVSS 8.2, scored by Vendor).
- This product type is often exposed to the internet, which is where attackers scan for it first.
- It has been in the catalogue for 612 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
VMware ESXi contains an arbitrary write vulnerability. A malicious actor with privileges within the VMX process may trigger an arbitrary kernel write leading to an escape of the sandbox.
Affected Versions
| Product | Versions |
|---|---|
| VMware ESXi | 8.0 to before ESXi80U3d-24585383 8.0 to before ESXi80U2d-24585300 7.0 to before ESXi70U3s-24585291 |
| VMware Cloud Foundation | 5.x, 4.5.x |
| VMware Telco Cloud Platform | 5.x, 4.x, 3.x, 2.x |
| VMware Telco Cloud Infrastructure | 3.x, 2.x |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for VMware ESXi. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vulnerability Management - 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
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