CVE-2020-3517

Name: CVE-2020-3517
Creator: NVD / NIST
Published: 2020-08-27T16:15:12.55+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.6/10EPSS 1.37%

Last modified Jun 17, 2026

CVE-2020-3517 is a high-severity vulnerability rated 8.6/10 on the CVSS scale. A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated attacker to cause process crashes, which could result in a denial of service (DoS) condition on an affected device. The attack vector is configuration dependent and could be remote or adjacent. EPSS estimates a 1.37% chance of exploitation in the next 30 days.

Description

A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated attacker to cause process crashes, which could result in a denial of service (DoS) condition on an affected device. The attack vector is configuration dependent and could be remote or adjacent. For more information about the attack vector, see the Details section of this advisory. The vulnerability is due to insufficient error handling when the affected software parses Cisco Fabric Services messages. An attacker could exploit this vulnerability by sending malicious Cisco Fabric Services messages to an affected device. A successful exploit could allow the attacker to cause a reload of an affected device, which could result in a DoS condition.

Metrics

CVSS 3.1

8.6/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

EPSS Probability

1.37%

68.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Cisco	Firepower Extensible Operating System	>= 1.1, < 1.1.4.179
Cisco	Firepower Extensible Operating System	>= 2.0, < 2.0.1.153
Cisco	Firepower Extensible Operating System	>= 2.1, < 2.1.1.86
Cisco	Firepower Extensible Operating System	>= 2.2, < 2.2.1.70
Cisco	Nx-Os	6.0\(2\)a3\(1\)
Cisco	Nx-Os	6.0\(2\)a3\(2\)
Cisco	Nx-Os	6.0\(2\)a3\(4\)
Cisco	Nx-Os	6.0\(2\)a4\(1\)
Cisco	Nx-Os	6.0\(2\)a4\(2\)
Cisco	Nx-Os	6.0\(2\)a4\(3\)
Cisco	Nx-Os	6.0\(2\)a4\(4\)
Cisco	Nx-Os	6.0\(2\)a4\(5\)
Cisco	Nx-Os	6.0\(2\)a4\(6\)
Cisco	Nx-Os	6.0\(2\)a6\(1\)
Cisco	Nx-Os	6.0\(2\)a6\(1a\)
Cisco	Nx-Os	6.0\(2\)a6\(2\)
Cisco	Nx-Os	6.0\(2\)a6\(2a\)
Cisco	Nx-Os	6.0\(2\)a6\(3\)
Cisco	Nx-Os	6.0\(2\)a6\(3a\)
Cisco	Nx-Os	6.0\(2\)a6\(4\)
Cisco	Nx-Os	6.0\(2\)a6\(4a\)
Cisco	Nx-Os	6.0\(2\)a6\(5\)
Cisco	Nx-Os	6.0\(2\)a6\(5a\)
Cisco	Nx-Os	6.0\(2\)a6\(5b\)
Cisco	Nx-Os	6.0\(2\)a6\(6\)
Cisco	Nx-Os	6.0\(2\)a6\(7\)
Cisco	Nx-Os	6.0\(2\)a6\(8\)
Cisco	Nx-Os	6.0\(2\)a7\(1\)
Cisco	Nx-Os	6.0\(2\)a7\(1a\)
Cisco	Nx-Os	6.0\(2\)a7\(2\)
Cisco	Nx-Os	6.0\(2\)a7\(2a\)
Cisco	Nx-Os	6.0\(2\)a8
Cisco	Nx-Os	6.0\(2\)a8\(1\)
Cisco	Nx-Os	6.0\(2\)a8\(2\)
Cisco	Nx-Os	6.0\(2\)a8\(3\)
Cisco	Nx-Os	6.0\(2\)a8\(4\)
Cisco	Nx-Os	6.0\(2\)a8\(4a\)
Cisco	Nx-Os	6.0\(2\)a8\(5\)
Cisco	Nx-Os	6.0\(2\)a8\(6\)
Cisco	Nx-Os	6.0\(2\)a8\(6.213\)
Cisco	Nx-Os	6.0\(2\)a8\(7\)
Cisco	Nx-Os	6.0\(2\)a8\(7a\)
Cisco	Nx-Os	6.0\(2\)a8\(7b\)
Cisco	Nx-Os	6.0\(2\)a8\(8\)
Cisco	Nx-Os	6.0\(2\)a8\(9\)
Cisco	Nx-Os	6.0\(2\)a8\(9.7\)
Cisco	Nx-Os	6.0\(2\)a8\(10\)
Cisco	Nx-Os	6.0\(2\)a8\(10a\)
Cisco	Nx-Os	6.0\(2\)a8\(11\)
Cisco	Nx-Os	6.0\(2\)a8\(11a\)

Showing 50 of 290 affected configurations. See NVD for the full list.

References

Timeline

Published: Aug 27, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-3517?

How severe is CVE-2020-3517?

CVE-2020-3517 has a CVSS score of 8.6/10 (HIGH severity). The EPSS model estimates a 1.37% probability of exploitation in the next 30 days.

How do I fix CVE-2020-3517?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-3517?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST