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Exploited in the wildUsed by ransomwareComputers & everyday appsCould reach you

CVE-2022-21999 Microsoft Windows: privilege escalation

In plain words: Something running with limited rights can promote itself to full control. Turns a small foothold (like a malicious app) into administrator or system-level access.

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

What to do

  1. Install Microsoft's security update for Windows. If no update exists, follow the vendor's workaround or stop using the product until one ships.
  2. Turn on automatic updates for the operating system and for Office, PDF and archive apps.
  3. Be careful with unexpected attachments — documents, .zip/.rar files and shortcuts are common bait.
  4. Use a normal (non-admin) account day to day and keep built-in protection like Microsoft Defender on.

Who is affected

Could reach you. Used in ransomware, which spreads to ordinary people and small businesses.

What's at risk: Your files, saved passwords and accounts. Many of these let a program that is already running gain full administrator control.

The details

Official name
Microsoft Windows Print Spooler Privilege Escalation Vulnerability
Product
Microsoft Windows
CISA description
Microsoft Windows Print Spooler contains an unspecified vulnerability which can allow for privilege escalation.
Type of flaw
Privilege escalation (CWE-40, CWE-1386)
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-2022-21999 ·

Questions about CVE-2022-21999

Is CVE-2022-21999 being exploited?

Yes. CISA added CVE-2022-21999 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-2022-21999?

Install Microsoft's security update for Windows. If no update exists, follow the vendor's workaround or stop using the product until one ships. Turn on automatic updates for the operating system and for Office, PDF and archive apps.

Am I affected by CVE-2022-21999?

Only if you use Microsoft Windows. Used in ransomware, which spreads to ordinary people and small businesses.

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