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  3. CVE-2025-20281
Exploited in the wildVPNs, firewalls & gatewaysWork IT

CVE-2025-20281 Cisco Identity Services Engine: 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 Aug 18, 2025

What to do

  1. Install Cisco's security update for Identity Services Engine. 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 Identity Services Engine Injection Vulnerability
Product
Cisco Identity Services Engine
CISA description
Cisco Identity Services Engine contains an injection vulnerability in a specific API of Cisco ISE and Cisco ISE-PIC due to insufficient validation of user-supplied input allowing an attacker to exploit this vulnerability by submitting a crafted API request. Successful exploitation could allow an attacker to perform remote code execution and obtaining root privileges on an affected device.
Type of flaw
Command or code injection (CWE-74)
Confirmed exploited
Jul 28, 2025
US federal patch deadline
Aug 18, 2025

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Answering about CVE-2025-20281 ·

Questions about CVE-2025-20281

Is CVE-2025-20281 being exploited?

Yes. CISA added CVE-2025-20281 to its Known Exploited Vulnerabilities catalog on Jul 28, 2025, which means there is reliable evidence of real-world attacks.

How do I fix CVE-2025-20281?

Install Cisco's security update for Identity Services Engine. 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-2025-20281?

Only if you use Cisco Identity Services Engine. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

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