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Known exploited · Cisco

CVE-2024-20399: Cisco NX-OS Command Injection Vulnerability

What it is

Cisco NX-OS contains a command injection vulnerability in the command line interface (CLI) that could allow an authenticated, local attacker to execute commands as root on the underlying operating system of an affected device.

Added July 2, 2024Due July 23, 2024CISA KEV catalog 2026.10.01

Vendor
Cisco
Product
NX-OS
Added to KEV
July 2, 2024
CISA due date
July 23, 2024
Ransomware use
Unknown

What CISA requires

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Forensic triage

No

What to do now

  1. Find every instance of NX-OS you run, including the forgotten ones, and check its version against the vendor advisory.
  2. Apply the vendor's fix or mitigation, before July 23, 2024 if you are bound by CISA's deadline, sooner if it faces the internet.
  3. Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
  4. Until every instance is patched, block the attack at the edge: a WAF in blocking mode stops OS command injection payloads, including Shellshock.

References

CVE-2024-20399 in the National Vulnerability Database

The Dome

Block it at the edge while you patch

The Dome's WAF runs the OWASP Core Rule Set in blocking mode and stops OS command injection payloads, including Shellshock before they reach your application.

See the Dome

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Source: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.