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NVD / CVE Program· CNA vmware

CVE-2021-22043: VMware ESXi contains a TOCTOU (Time-of-check Time-of-use) vulnerability that exists in the way temporary files are handled.

HighCVSS 7.5 · v3.1—No exploit No fix recorded

Noroxi assessment

Priority: Monitor (action score 30/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 1% (FIRST EPSS); higher than 64.7% of all records.
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. Special conditions such as timing or configuration are required.
  • According to the record, no fixed version is available yet.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Update when a fix is released; follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

VMware ESXi contains a TOCTOU (Time-of-check Time-of-use) vulnerability that exists in the way temporary files are handled. A malicious actor with access to settingsd, may exploit this issue to escalate their privileges by writing arbitrary files.

Published
Feb 16, 2022
Updated
Jun 16, 2026
EPSS
1.0% · 64th percentile

Report tools

JSON

Action score

30

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 1.0%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2021-22043

When you'll hear from us

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
vmwarefusion
vmwareesxi

Versions reported by the vendor

Affected version ranges reported by the assigning authority (vmware). Independent of NVD's CPE analysis and usually ahead of it.

  • n/a VMware ESXi and VMware Cloud Foundation

    • VMware ESXi(7.0 U3 before ESXi70U3c-19193900, 7.0 U2 before ESXi70U2e-19290878 and 7.0 U1 before ESXi70U1e-19324898) and VMware Cloud Foundation 4.x before 4.4affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • vmware esxi7.0
  • vmware fusionbefore 4.4

Same product

vmware: all records

Other highest-scoring records for the same primary product.

  • CVE-2020-3950VMware Fusion (11.x before 11.5.2), VMware Remote Console for Mac (11.x and prior before 11.0.1) and Horizon Client for Mac (5.x and prior…KEV
    63This week
  • CVE-2017-4901The drag-and-drop (DnD) function in VMware Workstation 12.x before version 12.5.4 and Fusion 8.x before version 8.5.5 has an out-of-bounds…
    45Plan
  • CVE-2019-5521VMware ESXi (6.7 before ESXi670-201904101-SG and 6.5 before ESXi650-201903001), Workstation (15.x before 15.0.3 and 14.x before 14.1.6) and…
    38Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2020-4004Nov 20, 2020 · VMware ESXi (7.0 before ESXi70U1b-17168206, 6.7 before ESXi670-202011101-SG, 6.5 before ESXi650-202011301-SG), Workstation (15.x before…
    32Monitor
  • ← EarlierCVE-2020-3960Sep 15, 2021 · VMware ESXi (6.7 before ESXi670-202006401-SG and 6.5 before ESXi650-202005401-SG), Workstation (15.x before 15.5.5), and Fusion (11.x…
    33Monitor
  • Later →CVE-2023-20871Apr 25, 2023 · VMware Fusion contains a local privilege escalation vulnerability.
    31Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
High
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-367 · Time-of-check Time-of-use (TOCTOU) Race Condition

CVSS vector

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records