#VU53914 Security restrictins bypass in Microsoft products - CVE-2021-31971

Vulnerability identifier: #VU53914

Vulnerability risk: Medium

CVSSv4.0: 4.5 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-31971

CWE-ID: CWE-264

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Windows Server
Operating systems & Components / Operating system
Windows
Operating systems & Components / Operating system
Microsoft Internet Explorer
Client/Desktop applications / Web browsers
Microsoft Edge
Client/Desktop applications / Web browsers

Vendor: Microsoft

Description

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to Windows HTML Platform does not properly impose security restrictions. A remote attacker can create a specially crafted web page, trick the victim into opening it and bypass implemented security restrictions.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Windows Server: 2008 R2 - 2008, 2012 R2 - 2012, 2016 10.0.14393.10, 2019 10.0.17763.1

Windows: 7, 8.1 RT - 8.1, 10 20H2 10.0.19042.572, 10 21H1 10.0.19043.985, 10 1607 10.0.14393.10, 10 1809 10.0.17763.1, 10 1909 10.0.18363.476, 10 2004 10.0.19041.264, 10

Microsoft Internet Explorer: 11

Microsoft Edge: All versions

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External links
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31971

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.