Vulnerability identifier: #VU29729
Vulnerability risk: Low
CVSSv3.1: 7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C]
CVE-ID:
CWE-ID:
CWE-119
Exploitation vector: Local
Exploit availability: No
Vulnerable software:
Skype for Business Server
Server applications /
Conferencing, Collaboration and VoIP solutions
Microsoft Lync
Client/Desktop applications /
Messaging software
Microsoft SharePoint Server
Server applications /
Application servers
Vendor: Microsoft
Description
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error when Microsoft SharePoint Server and Skype for Business Server improperly handle OAuth token validation. A local user can modify the token, trigger memory corruption and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Mitigation
Install update from vendor's website.
Vulnerable software versions
Skype for Business Server: 2015 CU8
Microsoft Lync:
Microsoft SharePoint Server: 2016 - 2019
Microsoft SharePoint Server: 2013
External links
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1025
Can this vulnerability be exploited remotely?
No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.
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.