Vulnerability identifier: #VU58069

Vulnerability risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-42305

CWE-ID: CWE-451

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Microsoft Exchange Server
Server applications / Mail servers

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 Microsoft Exchange Server. A remote attacker can spoof page content.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Microsoft Exchange Server: 2013 Cumulative Update 23 15.00.1497.002, 2019 Cumulative Update 10 15.02.0922.007 - 2019 Cumulative Update 11 15.02.0986.005, 2016 Cumulative Update 21 15.01.2308.008 - 2016 Cumulative Update 22 15.01.2375.007

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External links
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42305

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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.