Multiple vulnerabilities in Microsoft Exchange Server

Published: 2021-11-09 | Updated: 2022-07-30

Risk	Medium
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2021-41349 CVE-2021-42305
CWE-ID	CWE-451
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #1 is available.
Vulnerable software Subscribe	Microsoft Exchange Server Server applications / Mail servers
Vendor	Microsoft

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Spoofing attack

EUVDB-ID: #VU58068

Risk: Medium

CVSSv3.1: 5.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C]

CVE-ID: CVE-2021-41349

CWE-ID: CWE-451 - User Interface (UI) Misrepresentation of Critical Information (Clickjacking, spoofing)

Exploit availability: Yes

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 11 15.02.0986.005

External links

http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-41349

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.

2) Spoofing attack

EUVDB-ID: #VU58069