#VU50486 Spoofing attack in Skype for Business Server and Microsoft Lync - CVE-2021-24073

Vulnerability identifier: #VU50486

Vulnerability risk: Low

CVSSv4.0: 0.1 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-24073

CWE-ID: CWE-451

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Skype for Business Server
Server applications / Conferencing, Collaboration and VoIP solutions
Microsoft Lync
Client/Desktop applications / Messaging software

Vendor: Microsoft

Description

The vulnerability allows a remote attacker to perform spoofing attack.

The vulnerability exists due to incorrect processing of user-supplied data in Skype for Business and Lync. A remote authenticated attacker can spoof page content.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Skype for Business Server: 2015 CU8

Microsoft Lync: 2013

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External links
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-24073

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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