CVE-2021-31955 Microsoft Windows: information leak
In plain words: The program reveals information it should keep private. Leaked secrets — tokens, passwords or memory contents — that help a bigger attack.
Confirmed exploited by CISA on · US federal patch deadline Nov 17, 2021
What to do
- 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.
- Be careful with unexpected attachments — documents, .zip/.rar files and shortcuts are common bait.
- Use a normal (non-admin) account day to day and keep built-in protection like Microsoft Defender on.
Who is affected
Could reach you. This one is aimed at devices or apps of the kind people own.
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 Kernel Information Disclosure Vulnerability
- Product
- Microsoft Windows
- CISA description
- Microsoft Windows Kernel contains an unspecified vulnerability that allows for information disclosure. Successful exploitation allows attackers to read the contents of kernel memory from a user-mode process.
- Type of flaw
- Information leak (CWE-497)
- Confirmed exploited
- Nov 3, 2021
- US federal patch deadline
- Nov 17, 2021
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Answering about CVE-2021-31955 ·
Questions about CVE-2021-31955
Is CVE-2021-31955 being exploited?
Yes. CISA added CVE-2021-31955 to its Known Exploited Vulnerabilities catalog on Nov 3, 2021, which means there is reliable evidence of real-world attacks.
How do I fix CVE-2021-31955?
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-2021-31955?
Only if you use Microsoft Windows. This one is aimed at devices or apps of the kind people own.