SB2020120817 - Multiple vulnerabilities in Microsoft SharePoint
Published: December 8, 2020
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 6 secuirty vulnerabilities.
1) Input validation error (CVE-ID: CVE-2020-17121)
The vulnerability allows a remote attacker to execute arbitrary code on the system.
The vulnerability exists due to insufficient validation of user-supplied input in Microsoft SharePoint. A remote authenticated attacker can gain access to create a site and execute arbitrary code.
2) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2020-17089)
The vulnerability allows a remote authenticated attacker to escalate privileges on the system.
The vulnerability exists due to application does not properly impose security restrictions in Microsoft SharePoint, which leads to security restrictions bypass and privilege escalation.
3) Use-after-free (CVE-ID: CVE-2020-17125)
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a use-after-free error when processing Microsoft Excel files. A remote attacker can create a specially crafted Excel document, trick the victim into opening it, trigger memory corruption and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
4) Input validation error (CVE-ID: CVE-2020-17118)
The vulnerability allows a remote attacker to execute arbitrary code on the system.
The vulnerability exists due to insufficient validation of user-supplied input in Microsoft SharePoint. A remote attacker can execute arbitrary code on the target system.
5) Information disclosure (CVE-ID: CVE-2020-17120)
The vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output by the application in Microsoft SharePoint. A remote authenticated attacker can gain unauthorized access to sensitive information on the system.
6) Spoofing attack (CVE-ID: CVE-2020-17115)
The vulnerability allows a remote attacker to perform spoofing attack.
The vulnerability exists due to incorrect processing of user-supplied data in Microsoft SharePoint. A remote authenticated attacker can spoof page content.
Remediation
Install update from vendor's website.
References
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17121
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17089
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17125
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17118
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17120
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17115