CVE-2021-31166 Microsoft HTTP Protocol Stack Remote Code Execution
Remote attackers can execute arbitrary code via the Windows HTTP Protocol Stack, requiring immediate patching for Windows 10 and Server.
- Exploited in the wild
- Since 6 Apr 2022
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-31166?
CVE-2021-31166 is a critical use after free vulnerability in Microsoft Windows 10 20h2, published on 11 May 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
HTTP Protocol Stack Remote Code Execution Vulnerability
Weakness: CWE-416
Which versions are affected by CVE-2021-31166?
It affects 4 products.
Products include Microsoft Windows 10 2004, Microsoft Windows 10 20h2, Microsoft Windows Server 2004, Microsoft Windows Server 20h2.
How do I fix CVE-2021-31166?
No fix has been published for CVE-2021-31166 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 27 Apr 2022.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2021-31166 being exploited?
Yes. Attackers have exploited CVE-2021-31166 in the wild since at least 6 Apr 2022.
Public exploit code: 1 Metasploit module and 12 proofs of concept on GitHub.
Other vulnerabilities in Microsoft Windows 10 20h2
Sources
Also known as GHSA-3mj9-c62w-jw5w.