Known exploited · VMware
CVE-2025-22225: VMware ESXi Arbitrary Write Vulnerability
What it is
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.
- Vendor
- VMware
- Product
- ESXi
- Added to KEV
- March 4, 2025
- CISA due date
- March 25, 2025
- Ransomware use
- Known
What CISA requires
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Forensic triage
No
What to do now
- Find every instance of ESXi you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before March 25, 2025 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.