CVE-2021-1361
highpriority · track · 37EPSS 0.016 · 76 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the implementation of an internal file management service for Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode that are running Cisco NX-OS Software could allow an unauthenticated, remote attacker to create, delete, or overwrite arbitrary files with root privileges on the device. This vulnerability exists because TCP port 9075 is incorrectly configured to listen and respond to external connection requests. An attacker could exploit this vulnerability by sending crafted TCP packets to an IP address that is configured on a local interface on TCP port 9075. A successful exploit could allow the attacker to create, delete, or overwrite arbitrary files, including sensitive files that are related to the device configuration. For example, the attacker could add a user account without the device administrator knowing.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco NX-OS Software 9.3(5) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 9.3(5) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 9.3(5w) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 9.3(5w) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 9.3(6) when installed on Cisco Nexus 3000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco NX-OS Software 9.3(6) when installed on Cisco Nexus 9000 Series Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.3–9.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (11)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-3000-9000-fileaction-QtLzDRy2Cisco NX-OS Software Unauthenticated Arbitrary File Actions Vulnerability2021-02-24csaf · cisco_csafUS
A vulnerability in the implementation of an internal file management service for Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode that are running Cisco NX-OS Software could allow an unauthenticated, remote attacker to create, delete, or overwrite arbitrary files with root privileges on the device. This vulnerability exists because TCP port 9075 is incorrectly configured to listen and respond to external connection requests. An attacker could exploit this vulnerability by sending crafted TCP packets to an IP address that is configured on a local interface on TCP port 9075. A successful exploit could allow the attacker to create, delete, or overwrite arbitrary files, including sensitive files that are related to the device configuration. For example, the attacker could add a user account without the device administrator knowing. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is part of the February 2021 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: February 2021 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74414"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- https://nvd.nist.gov/vuln/detail/CVE-2021-1361cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-3000-9000-fileaction-QtLzDRy2cnnvd
- https://vigilance.fr/vulnerability/Cisco-Nexus-3000-9000-read-write-access-via-9075-tcp-34669cnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.0705cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-3000-9000-fileaction-QtLzDRy2enisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-3000-9000-fileaction-QtLzDRy2Vendor Advisorynvd
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