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Threats / VMware / CVE-2025-22225
CVE-2025-22225 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

VMware ESXi vulnerability

VMware ESXi arbitrary write vulnerability allows privileged VMX process attackers to write to kernel memory and escape the sandbox environment.

Verdict

Today item, not a backlog item.

A privilege escalation and sandbox escape vulnerability in VMware ESXi that enables arbitrary kernel writes from within the VMX process context, facilitating host compromise and lateral movement in virtualized environments.

CISA KEV Yes · 2025-03-043Ransomware use Flagged3EPSS 0.00963 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
11 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-03-04), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.00963 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: VMware, ESXi. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-123 CWE-123.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I gain initial access to a guest VM or VMX process with limited privileges.
Business
Guest VM compromise represents initial foothold in customer infrastructure.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I exploit the arbitrary write vulnerability to write malicious data to kernel memory.
Business
Kernel memory corruption enables escape from guest isolation boundaries.
3

Lateral reach — past segmentation narrative 3

Attacker
I break out of the VMX sandbox and achieve code execution on the ESXi host.
Business
Host compromise grants attacker control over all guest VMs and stored data.
4

Data at risk — exfiltration narrative 4

Attacker
I establish persistence and move laterally across the virtualized infrastructure.
Business
Multi-VM compromise and data exfiltration across the entire virtual environment.
5

Lights out — disruption & extortion narrative 5

Attacker
I deploy ransomware or destructive payloads across compromised hosts and guests.
Business
Widespread service disruption, data encryption, and operational downtime across customer infrastructure.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • Ransomware-use flag (CISA)
  • EPSS probability (FIRST)
  • 11 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by vmware (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by vmwareCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.