Vulnerability

CVE-2023-20867

Low· 3.9KEVCVSS3.9EPSS2%

.rules3/5

VMware Tools Authentication Bypass Vulnerability

VMware Tools contains an authentication bypass vulnerability in the vgauth module. A fully compromised ESXi host can force VMware Tools to fail to authenticate host-to-guest operations, impacting the confidentiality and integrity of the guest virtual machine. An attacker must have root access over ESXi to exploit this vulnerability.

Threat signal

49/100

Elevated

Severity

low

CVSS

3.9

EPSS

Active

KEV

CISA KEV — actively exploited

1065d overdue

AffectedVMware — Tools

Added to KEV

2023-06-23

Federal patch due (BOD 22-01)

2023-07-14

Required action (CISA verbatim)

Apply updates per vendor instructions.

Vendor advisory + references

CISA description: “VMware Tools contains an authentication bypass vulnerability in the vgauth module. A fully compromised ESXi host can force VMware Tools to fail to authenticate host-to-guest operations, impacting the confidentiality and integrity of the guest virtual machine. An attacker must have root access over ESXi to exploit this vulnerability.”

CVSS

v3.1Open in FIRST calculator →

3.9/ 10LOWCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N

Attack VectorLocalRequires local access — shell, console, or local app.
Attack ComplexityHighRequires conditions outside attacker's control (race, brute-force, configuration
Privileges RequiredHighAdmin / root privileges required.
User InteractionNoneFully automated — no victim action needed.
ScopeChangedImpact extends beyond the vulnerable component (e.g. sandbox escape).
Confidentiality ImpactLowSome data disclosure; attacker doesn't fully control what.
Integrity ImpactLowSome data modification; attacker doesn't fully control extent.
Availability ImpactNoneNo availability impact.

EPSS

Exploit prediction · 30-day horizonFIRST.org →

2.19%

probability of exploitation in next 30 days

p85

higher than 85% of all CVEs

3-day trend↑ 0pp

Mid-pack — moderate exploitation likelihood.

Vendor VEX

No VEX statements published for CVE-2023-20867. Vendors publish VEX (Vulnerability Exploitability eXchange) to assert per-product whether a CVE is actually exploitable in their distribution.

SSVCAttend

Active exploitation with limited impact — coordinate patching

exploitation: active
automatable: no
impact: partial
mission: support

Lifecycle

2023-06-23Added to CISA KEVransomware: Unknown
2023-06-23Published
2023-07-14Federal patch due (BOD 22-01)
2023-07-19Vendor advisory · amazon-linuxALAS2-2023-2139 — ALAS2-2023-2139 (low): open-vm-tools
2026-06-12Last modified1 source

Entity graph

2 nodes · 1 edges · click to pivot

CVEActorVendor advisoryIOCNews

Vendor advisories

amazon-linuxALAS2-2023-2139ALAS2-2023-2139 (low): open-vm-tools

No source-event history recorded yet. New revisions will appear here as ingestors re-fetch this CVE.