SRC-2020-0021 : Microsoft SharePoint Server SPHashtagHelper MakeOLSGetRequest Server-Side Request Forgery Information Disclosure Vulnerability
This vulnerability allows remote attackers disclose information and/or escalate privileges under certain conditions. Authentication is required to exploit this vulnerability.
The specific flaw exists within the CallOLS function inside of the SPHashtagStoreManager class. The issue results from the lack of proper validation of user-supplied url parameter when performing web requests. An attacker can leverage this vulnerability to execute arbitrary web requests to protected resources.
Microsoft has issued an update to correct this vulnerability. More details can be found at:
- 2020-07-06 – Sent to Microsoft
- 2020-09-08 – Coordinated public release of advisory
This vulnerability was discovered by Steven Seeley (mr_me) of Qihoo 360 Vulcan Team