#VU29785 Cross-site scripting in Office Online Server and Microsoft Office Web Apps - CVE-2020-1442

Vulnerability identifier: #VU29785

Vulnerability risk: Low

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

CVE-ID: CVE-2020-1442

CWE-ID: CWE-79

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Office Online Server
Server applications / Other server solutions
Microsoft Office Web Apps
Client/Desktop applications / Office applications

Vendor: Microsoft

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data in the Office Web Apps server. A remote authenticated attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Office Online Server : 2016

Microsoft Office Web Apps: 2013 Service Pack 1

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External links
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1442

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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. However, proof of concept for this vulnerability is available.