CVE-2025-41237
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedVMware ESXi, Workstation, and Fusion contain an integer-underflow in VMCI (Virtual Machine Communication Interface) that leads to an out-of-bounds write. A malicious actor with local administrative privileges on a virtual machine may exploit this issue to execute code as the virtual machine's VMX process running on the host. On ESXi, the exploitation is contained within the VMX sandbox whereas, on Workstation and Fusion, this may lead to code execution on the machine where Workstation or Fusion is installed.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceInteger underflow in VMware's Virtual Machine Communication Interface (VMCI) leads to an out-of-bounds write. A malicious actor with local administrative privileges on a virtual machine can exploit this to execute code as the VMX process on the host. On ESXi, exploitation is contained within the VMX sandbox; on Workstation and Fusion, this allows code execution on the host machine.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify the VMware product in useDetermine if the system runs ESXi (bare-metal hypervisor), Workstation (Windows/Linux desktop), or Fusion (macOS desktop). On ESXi, use 'vmware -l' or check the ESXi host client version. On Workstation, run 'vmware -v' or check Help > About. On Fusion, check Fusion > About Fusion.Affected if The product is VMware ESXi, Workstation, or Fusion without current security patches applied.
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Check the installed VMware versionCompare your current version against the affected version ranges. On ESXi, run 'vmware -v' or check the vSphere Client. On Workstation/Fusion, run 'vmware -v' from command line or view Help > About VMware. Obtain the exact version and build numbers.Affected if The installed version falls within the unpatched version range for this CVE.
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Verify if VMCI is present and enabledCheck the virtual machine's configuration file (.vmx) for VMCI-related settings. Look for entries such as 'vmci0.present = "TRUE"' or similar VMCI device configuration. On ESXi, you can also check via 'vim-cmd vmsvc/get.config <vm_id>' or the vSphere Client VM settings.Affected if VMCI is present and enabled in the virtual machine configuration (vmci0.present = TRUE or equivalent setting exists).
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Confirm guest VM has administrative privilegesThis vulnerability requires an attacker with local administrative privileges on the guest virtual machine. Review the VM user permissions and verify who has admin rights inside the guest OS.Affected if Non-trusted users have administrative privileges inside the guest virtual machine, providing a potential attacker path to exploit the VMCI flaw.
You are affected if you run an unpatched version of ESXi, Workstation, or Fusion WITH VMCI enabled, and untrusted users have administrative access to guest virtual machines.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataApply VMware security patches when released; until then, restrict local administrative privileges on VMs and minimize the number of users with such access.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-41237 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2025-41237 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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