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  3. CVE-2021-22941
Exploited in the wildUsed by ransomwareVPNs, firewalls & gatewaysWork IT

CVE-2021-22941 Citrix ShareFile: login or permission bypass

In plain words: A door that should be locked is not: part of the system can be reached without a valid login or permission. The attacker gets in as a user or administrator without knowing a password.

Confirmed exploited by CISA on · US federal patch deadline Apr 15, 2022

What to do

  1. Install Citrix's security update for ShareFile. 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.

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
Citrix ShareFile Improper Access Control Vulnerability
Product
Citrix ShareFile
CISA description
Improper Access Control in Citrix ShareFile storage zones controller may allow an unauthenticated attacker to remotely compromise the storage zones controller.
Type of flaw
Login or permission bypass (CWE-284)
Confirmed exploited
Mar 25, 2022 — known to be used in ransomware attacks
US federal patch deadline
Apr 15, 2022

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Answering about CVE-2021-22941 ·

Questions about CVE-2021-22941

Is CVE-2021-22941 being exploited?

Yes. CISA added CVE-2021-22941 to its Known Exploited Vulnerabilities catalog on Mar 25, 2022, which means there is reliable evidence of real-world attacks, including by ransomware groups.

How do I fix CVE-2021-22941?

Install Citrix's security update for ShareFile. 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-2021-22941?

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

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