Guest-to-host code execution via undersized VMXNET3 buffer
Published Jul 15, 2025 · Updated Feb 26, 2026
Integer overflow in VMware ESXi, Workstation, and Fusion allows guest OS users to execute host code through the VMXNET3 adapter. VMXNET3 fails to validate user-supplied size data before buffer allocation, so integer overflow produces an undersized buffer and an out-of-bounds write. Exploitation requires administrative code execution in a guest configured with VMXNET3; guests using other virtual adapters are unaffected.
Summary
What happened
Integer overflow in VMware ESXi, Workstation, and Fusion allows guest OS users to execute host code through the VMXNET3 adapter. VMXNET3 fails to validate user-supplied size data before buffer allocation, so integer overflow produces an undersized buffer and an out-of-bounds write. Exploitation requires administrative code execution in a guest configured with VMXNET3; guests using other virtual adapters are unaffected.
The record
- CVE
- CVE-2025-41236
- Published
- Jul 15, 2025
- Updated
- Feb 26, 2026
- Vendor
- VMware
- Product
- VMware Workstation
- Classifications
- CWE-787, T1068
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Jul 15, 2025CVE publishedPublication date reported by the CVE source.
- Feb 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=17.x <17.6.4
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Reported exploitation
- Pwn2Own VMXNET3 guest-to-host demonstrationreported exploitation
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo