CVE-2021-1390

A vulnerability in one of the diagnostic test CLI commands of Cisco IOS XE Software could allow an authenticated, local attacker to execute arbitrary code on an affected device. To exploit this vulnerability, the attacker would need to have valid user credentials at privilege level 15. This vulnerability exists because the affected software permits modification of the run-time memory of an affected device under specific circumstances. An attacker could exploit this vulnerability by authenticating to the affected device and issuing a specific diagnostic test command at the CLI. A successful exploit could trigger a logic error in the code that was designed to restrict run-time memory modifications. The attacker could take advantage of this logic error to overwrite system memory locations and execute arbitrary code on the underlying Linux operating system (OS) of the affected device.

• CWE-123

• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-XE-OFP-6Nezgn7bVendor Advisory
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-XE-OFP-6Nezgn7bVendor Advisory

Published

Mar 24, 2021

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2021-1384A vulnerability in Cisco IOx application hosting environment…7.2
• CVE-2021-1385A vulnerability in the Cisco IOx application hosting environ…6.5
• CVE-2021-1386A vulnerability in the dynamic link library (DLL) loading me…7.8
• CVE-2021-1387A vulnerability in the network stack of Cisco NX-OS Software…8.6
• CVE-2021-1388A vulnerability in an API endpoint of Cisco ACI Multi-Site O…10
• CVE-2021-1389A vulnerability in the IPv6 traffic processing of Cisco IOS …6.5
• CVE-2021-1391A vulnerability in the dragonite debugger of Cisco IOS XE So…6.7
• CVE-2021-1392A vulnerability in the CLI command permissions of Cisco IOS …7.8
• CVE-2021-1393Multiple vulnerabilities in Cisco Application Services Engin…9.8
• CVE-2021-1394A vulnerability in the ingress traffic manager of Cisco IOS …5.3
• CVE-2021-1395A vulnerability in the web-based management interface of Cis…6.1
• CVE-2021-1396Multiple vulnerabilities in Cisco Application Services Engin…6.5