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  3. CVE-2024-20399
Exploited in the wildVPNs, firewalls & gatewaysWork IT

CVE-2024-20399 Cisco NX-OS: command or code injection

In plain words: The program treats text it receives as instructions instead of plain data. The attacker can run commands on the machine — often the whole device is taken over.

Confirmed exploited by CISA on · US federal patch deadline Jul 23, 2024

What to do

  1. Install Cisco's security update for NX-OS. If no update exists, follow the vendor's workaround or stop using the product until one ships.
  2. Patch edge devices first — attackers often start scanning for them within hours of a fix.
  3. Never expose the device's admin page to the internet.
  4. After patching a device that was exposed, follow the vendor's compromise checks, end active sessions and change passwords.

Read Cisco's advisory ↗

Who is affected

Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

What's at risk: They face the internet and guard the whole network, so a flaw here can hand attackers a way in — and these devices usually run no antivirus, so break-ins go unnoticed.

The details

Official name
Cisco NX-OS Command Injection Vulnerability
Product
Cisco NX-OS
CISA description
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.
Type of flaw
Command or code injection (CWE-78)
Confirmed exploited
Jul 2, 2024
US federal patch deadline
Jul 23, 2024

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Answering about CVE-2024-20399 ·

Questions about CVE-2024-20399

Is CVE-2024-20399 being exploited?

Yes. CISA added CVE-2024-20399 to its Known Exploited Vulnerabilities catalog on Jul 2, 2024, which means there is reliable evidence of real-world attacks.

How do I fix CVE-2024-20399?

Install Cisco's security update for NX-OS. If no update exists, follow the vendor's workaround or stop using the product until one ships. Patch edge devices first — attackers often start scanning for them within hours of a fix.

Am I affected by CVE-2024-20399?

Only if you use Cisco NX-OS. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

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