Denial of service in Microsoft Outlook

Published: 2022-08-09 | Updated: 2022-08-18
Risk Medium
Patch available YES
Number of vulnerabilities 1
CVE-ID CVE-2022-35742
Exploitation vector Network
Public exploit N/A
Vulnerable software
Microsoft Outlook
Client/Desktop applications / Office applications

Microsoft Office
Client/Desktop applications / Office applications

Microsoft 365 Apps for Enterprise
Client/Desktop applications / Office applications

Microsoft Office LTSC 2021
Other software / Other software solutions

Vendor Microsoft

Security Bulletin

This security bulletin contains one medium risk vulnerability.

1) Heap-based buffer overflow

EUVDB-ID: #VU66320

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2022-35742

CWE-ID: CWE-122 - Heap-based Buffer Overflow

Exploit availability: No


The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input in Microsoft Outlook when handling MIME headers. A remote attacker can send a specially crafted email to the victim and trigger heap corruption every time the email is processed by the application.

Successful exploitation may result in a perform a persistent denial-of-service condition.


Install updates from vendor's website.

Vulnerable software versions

Microsoft Outlook: 2013 RT Service Pack 1 - 2016

Microsoft Office LTSC 2021: 32 bit editions - 64 bit editions

Microsoft Office: 2019

Microsoft 365 Apps for Enterprise: 32-bit Systems - 64-bit Systems

External links

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 trick the victim to visit a specially crafted website or open a file.

Is there known malware, which exploits this vulnerability?

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