CVE-2017-4933

VMware ESXi (6.5 before ESXi650-201710401-BG), Workstation (12.x before 12.5.8), and Fusion (8.x before 8.5.9) contain a vulnerability that could allow an authenticated VNC session to cause a heap overflow via a specific set of VNC packets resulting in heap corruption. Successful exploitation of this issue could result in remote code execution in a virtual machine via the authenticated VNC session. Note: In order for exploitation to be possible in ESXi, VNC must be manually enabled in a virtual machine's .vmx configuration file. In addition, ESXi must be configured to allow VNC traffic through the built-in firewall.

Published: 2017-12-20 Last update: 2026-05-13 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2017-4933 is rated Moderate Risk (62.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 3.57%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-4933

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 7.08% 3.57% -3.51%
2 2025-11-21 6.07% 7.08% +1.01%
3 2025-11-18 6.07%

Full EPSS history (19 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-4933

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]
6.0 2.0 MEDIUM
AV:N/AC:M/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
6.8 6.4 [email protected]

Weakness enumeration for CVE-2017-4933

Affected software / configurations for CVE-2017-4933

Vendor Product Version Raw CPE
vmware workstation_pro >= 12.0.0, < 12.5.8 cpe:2.3:a:vmware:workstation_pro:*:*:*:*:*:*:*:*
vmware workstation_pro 14.0 cpe:2.3:a:vmware:workstation_pro:14.0:*:*:*:*:*:*:*
vmware workstation_pro 14.1.0 cpe:2.3:a:vmware:workstation_pro:14.1.0:*:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:-:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201701001:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201703001:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201703002:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201704001:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707101:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707102:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707103:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707201:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707202:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707203:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707204:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707205:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707206:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707207:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707208:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707209:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707210:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707211:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707212:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707213:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707214:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707215:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707216:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707217:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707218:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707219:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707220:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201707221:*:*:*:*:*:*
vmware esxi 6.5 cpe:2.3:o:vmware:esxi:6.5:650-201710001:*:*:*:*:*:*
vmware fusion >= 8.0.0, < 8.5.9 cpe:2.3:a:vmware:fusion:*:*:*:*:*:*:*:*

References for CVE-2017-4933

URL Tags
http://www.securitytracker.com/id/1040024 Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1040025 Third Party Advisory VDB Entry
https://www.vmware.com/security/advisories/VMSA-2017-0021.html Issue Tracking Vendor Advisory
cvelogic Threat Intelligence