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  3. CVE-2026-54420
Exploited in the wildServers & business softwareWork IT

CVE-2026-54420 LiteSpeed cPanel Plugin: software flaw

In plain words: A mistake in the software that attackers have found a way to abuse. Depends on the product — see the description and the vendor advisory.

Confirmed exploited by CISA on · US federal patch deadline Jun 18, 2026

What to do

  1. Install LiteSpeed's security update for cPanel Plugin. If no update exists, follow the vendor's workaround or stop using the product until one ships.
  2. Keep a list of every internet-facing server you run so nothing is forgotten.
  3. Patch anything in this catalog first, ahead of normal patch cycles.
  4. Put admin and file-transfer apps behind a VPN or single sign-on instead of the open internet.

Read LiteSpeed'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: Mass data theft and ransomware: a single flaw in a file-transfer or email server has exposed thousands of organisations at once.

The details

Official name
LiteSpeed cPanel Plugin UNIX Symbolic Link (Symlink) Following Vulnerability
Product
LiteSpeed cPanel Plugin
CISA description
LiteSpeed cPanel plugin contains a UNIX symbolic link (Symlink) following vulnerability that could allow a user with FTP or web shell access on a shared hosting server running CloudLinux/CageFS.
Type of flaw
Software flaw (CWE-61)
Confirmed exploited
Jun 15, 2026
US federal patch deadline
Jun 18, 2026

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Answering about CVE-2026-54420 ·

Questions about CVE-2026-54420

Is CVE-2026-54420 being exploited?

Yes. CISA added CVE-2026-54420 to its Known Exploited Vulnerabilities catalog on Jun 15, 2026, which means there is reliable evidence of real-world attacks.

How do I fix CVE-2026-54420?

Install LiteSpeed's security update for cPanel Plugin. If no update exists, follow the vendor's workaround or stop using the product until one ships. Keep a list of every internet-facing server you run so nothing is forgotten.

Am I affected by CVE-2026-54420?

Only if you use LiteSpeed cPanel Plugin. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.

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