VMware ESXi and Workstation TOCTOU Race Condition
CVE-2025-22224 is a high-severity time-of-check time-of-use (TOCTOU) race condition vulnerability in ESXi from VMware, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited with local access to the system by an attacker with administrator privileges, without any action from a user. The record lists versions ESXi80U3d-24585383, ESXi80U2d-24585300, ESXi70U3s-24585291 as the first without the flaw, so updating ESXi to one of those releases or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on March 4, 2025, which means attacks have been observed in the wild.
Attackers are already exploiting this vulnerability, according to CISA.
What to do
- Update ESXi to ESXi80U3d-24585383 or ESXi80U2d-24585300 or ESXi70U3s-24585291, whichever matches your release line, or a later version.
- Update Workstation to 17.6.3 or a later version.
- CISA's required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- Read the advisory on support.broadcom.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| VMware | ESXi | 8.0 up to, but not including, ESXi80U3d-24585383; 8.0 up to, but not including, ESXi80U2d-24585300; 7.0 up to, but not including, ESXi70U3s-24585291 | ESXi80U3d-24585383, ESXi80U2d-24585300, ESXi70U3s-24585291 |
| VMware | Workstation | 17.x up to, but not including, 17.6.3 | 17.6.3 |
| VMware | VMware Cloud Foundation | 5.x, 4.5.x | Not stated |
| VMware | Telco Cloud Platform | 5.x, 4.x, 3.x, 2.x | Not stated |
| VMware | Telco Cloud Infrastructure | 3.x, 2.x | Not stated |
| VMware | Cloud Foundation | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- HighAdministrator-level access is required first.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.3 | Critical | CNA (vmware.com) |
| CVSS 3.1 | 8.2 | High | NVD |
Official description
VMware ESXi, and Workstation contain a TOCTOU (Time-of-Check Time-of-Use) vulnerability 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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Time-of-check Time-of-use (TOCTOU) Race Condition
The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
How developers prevent this class of flaw
- The most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.
- When the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.
- Limit the interleaving of operations on files from multiple processes.
More Time-of-check Time-of-use (TOCTOU) Race Condition vulnerabilities (CWE-367)
Timeline
- CVE record published.
- Added to CISA's Known Exploited Vulnerabilities catalogue.
- CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
- Deadline for US federal agencies to remediate, set by CISA.
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-22224US Government Resource
Other vulnerabilities in ESXi
- 2.7 Low severity
Broadcom VMWare ESX Insufficient Logging Exploited
- 7.1 High severity
- 9.3 Critical severity
- 9.3 Critical severity
- 9.3 Critical severity
- 8.2 High severity
VMware ESXi Arbitrary Write Exploited
Recent Time-of-check Time-of-use (TOCTOU) Race Condition vulnerabilities
- 7.5 High severity
- 8.1 High severity
- 7.0 High severity
- 7.8 High severity
- 8.1 High severity
- 9.8 Critical severity
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