← Vulnerability feed

Vulnerability record · CVE-2020-3517 · published 27 August 2020

CVE-2020-3517: Cisco firepower extensible operating system null pointer dereference vulnerability

Cisco · Firepower Extensible Operating System

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.

8.6 CVSS 3.1 High EPSS 1.4% · top 28.9% CWE-476 · NULL pointer dereference
8.6CVSS 3.1 base score, v2 7.8
1.4%EPSS exploitation probability, 30 days
NoNot in CISA KEV
2Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

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.

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

Affected products

2 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fxos-nxos-cfs-dos-dAmnymbd Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fxos-nxos-cfs-dos-dAmnymbd Vendor Advisory

Track CVE-2020-3517 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

6.7CVE-2024-20399Cisco NX-OS CLI command injection allows root command executionCisco NX-OS fails to properly validate arguments passed to specific configuration CLI commands, allowing OS command injection. An attacker who alread…KEVEPSS 4.3%analysed9.8CVE-2018-0310Cisco nx-os out-of-bounds read vulnerabilityA vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacke…EPSS 4.1%9.8CVE-2018-0301Cisco nx-os improper input validation vulnerabilityA vulnerability in the NX-API feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to craft a packet to the management int…EPSS 17%9.8CVE-2016-1453Cisco nx-os memory buffer overflow vulnerabilityBuffer overflow in the Overlay Transport Virtualization (OTV) GRE feature in Cisco NX-OS 5.0 through 7.3 on Nexus 7000 and 7700 devices allows remote…EPSS 8.1%9.8CVE-2016-1341Cisco nx-os permissions and access controls vulnerabilityCisco NX-OS 7.0(1)N1(1), 7.0(1)N1(3), and 7.0(4)N1(1) on Nexus 2000 Fabric Extender devices has a blank root password, which allows local users to ga…EPSS 1.1%9.8CVE-2015-6435Cisco firepower extensible operating system os command injection vulnerabilityAn unspecified CGI script in Cisco FX-OS before 1.1.2 on Firepower 9000 devices and Cisco Unified Computing System (UCS) Manager before 2.2(4b), 2.2(…EPSS 8.7%9.1CVE-2021-1361Cisco nx-os vulnerabilityA vulnerability in the implementation of an internal file management service for Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switche…EPSS 1.6%9.0CVE-2015-4235Cisco application policy infrastructure controller \(apic\) permissions and access controls vulnerabilityCisco Application Policy Infrastructure Controller (APIC) devices with software before 1.0(3o) and 1.1 before 1.1(1j) and Nexus 9000 ACI devices with…EPSS 2.2%

Source: NIST National Vulnerability Database (record CVE-2020-3517), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.