How severe is CVE-2013-1661?

CVE-2013-1661 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2013-1661 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-1661?

CVE-2013-1661 primarily affects Vmware Esx. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2013-1661?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2013-1661 published?

CVE-2013-1661 was published on 2013-09-04 and last updated on 2026-06-16.

CVE-2013-1661

CVE-2013-1661 is a medium-severity vulnerability in Vmware Esx with a CVSS 2.0 base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 2.0 base score 4.3)
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Vmware Esx
Published: 2013-09-04
Last modified: 2026-06-16

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2013-1661?: CVE-2013-1661 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2013-1661 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-1661?: CVE-2013-1661 primarily affects Vmware Esx. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-1661?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2013-1661 published?: CVE-2013-1661 was published on 2013-09-04 and last updated on 2026-06-16.

References

http://www.vmware.com/security/advisories/VMSA-2013-0011.html

Affected products (14)

cpe:2.3:o:vmware:esx:4.0:*:*:*:*:*:*:*
cpe:2.3:o:vmware:esx:4.1:*:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:4.0:*:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:4.0:1:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:4.0:2:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:4.0:3:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:4.0:4:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:4.1:*:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:4.1:1:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:4.1:2:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:5.0:*:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:5.0:1:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:5.0:2:*:*:*:*:*:*
cpe:2.3:o:vmware:esxi:5.1:*:*:*:*:*:*:*

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