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  3. CVE-2026-20045
Exploited in the wildVPNs, firewalls & gatewaysWork IT

CVE-2026-20045 Cisco Unified Communications Manager: 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 Feb 11, 2026

What to do

  1. Install Cisco's security update for Unified Communications Manager. 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 Unified Communications Products Code Injection Vulnerability
Product
Cisco Unified Communications Manager
CISA description
Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unity Connection, and Cisco Webex Calling Dedicated Instance contain a code injection vulnerability that could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to root.
Type of flaw
Command or code injection (CWE-94)
Confirmed exploited
Jan 21, 2026
US federal patch deadline
Feb 11, 2026

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Answering about CVE-2026-20045 ·

Questions about CVE-2026-20045

Is CVE-2026-20045 being exploited?

Yes. CISA added CVE-2026-20045 to its Known Exploited Vulnerabilities catalog on Jan 21, 2026, which means there is reliable evidence of real-world attacks.

How do I fix CVE-2026-20045?

Install Cisco's security update for Unified Communications Manager. 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-2026-20045?

Only if you use Cisco Unified Communications Manager. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

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