#VU53101 Out-of-bounds write in Web Media Extensions - CVE-2021-28465

Vulnerability identifier: #VU53101

Vulnerability risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-28465

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Web Media Extensions
Other software / Other software solutions

Vendor: Microsoft

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing untrusted input within Falc decoder in Microsoft Web Media Extension. A remote attacker can create a specially crafted file, trick the victim into opening it using the affected software, trigger out-of-bounds write and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Web Media Extensions: All versions

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External links
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-28465
https://fortiguard.com/zeroday/FG-VD-21-011

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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.