#VU27736 Input validation error in Microsoft SharePoint Server - CVE-2020-1102

Vulnerability identifier: #VU27736

Vulnerability risk: Medium

CVSSv4.0: 7.4 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2020-1102

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Microsoft SharePoint Server
Server applications / Application servers

Vendor: Microsoft

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists in Microsoft SharePoint when handling shared forms. A remote authenticated attacker can invoke a shared form in a way that allows arbitrary controls to be instantiated and execute arbitrary code in the context of the SharePoint application pool and the SharePoint server farm account.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Microsoft SharePoint Server: 2016 - 2019

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External links
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1102
https://www.zerodayinitiative.com/advisories/ZDI-20-648/

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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.