CVE-2013-1661

VMware ESXi 4.0 through 5.1, and ESX 4.0 and 4.1, does not properly implement the Network File Copy (NFC) protocol, which allows man-in-the-middle attackers to cause a denial of service (unhandled exception and application crash) by modifying the client-server data stream.

Published: 2013-09-04 Last update: 2026-04-29 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2013-1661 is rated Low Risk (36.5/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.36%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2013-1661

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 2025-03-30 0.53% 0.36% -0.17%
2 2025-03-29 0.36% 0.53% +0.17%
3 2025-03-19 — 0.36% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2013-1661

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:N/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:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2013-1661

Affected software / configurations for CVE-2013-1661

Vendor Product Version Raw CPE
vmware esx 4.0 cpe:2.3:o:vmware:esx:4.0:*:*:*:*:*:*:*
vmware esx 4.1 cpe:2.3:o:vmware:esx:4.1:*:*:*:*:*:*:*
vmware esxi 4.0 cpe:2.3:o:vmware:esxi:4.0:*:*:*:*:*:*:*
vmware esxi 4.0 cpe:2.3:o:vmware:esxi:4.0:1:*:*:*:*:*:*
vmware esxi 4.0 cpe:2.3:o:vmware:esxi:4.0:2:*:*:*:*:*:*
vmware esxi 4.0 cpe:2.3:o:vmware:esxi:4.0:3:*:*:*:*:*:*
vmware esxi 4.0 cpe:2.3:o:vmware:esxi:4.0:4:*:*:*:*:*:*
vmware esxi 4.1 cpe:2.3:o:vmware:esxi:4.1:*:*:*:*:*:*:*
vmware esxi 4.1 cpe:2.3:o:vmware:esxi:4.1:1:*:*:*:*:*:*
vmware esxi 4.1 cpe:2.3:o:vmware:esxi:4.1:2:*:*:*:*:*:*
vmware esxi 5.0 cpe:2.3:o:vmware:esxi:5.0:*:*:*:*:*:*:*
vmware esxi 5.0 cpe:2.3:o:vmware:esxi:5.0:1:*:*:*:*:*:*
vmware esxi 5.0 cpe:2.3:o:vmware:esxi:5.0:2:*:*:*:*:*:*
vmware esxi 5.1 cpe:2.3:o:vmware:esxi:5.1:*:*:*:*:*:*:*

References for CVE-2013-1661

cvelogic Threat Intelligence