SRC-2022-0004 : Microsoft SharePoint Server SPWebRequest SafeCreate TOCTOU DNS Rebinding Security Feature Bypass Vulnerability

Vulnerability Details:

This vulnerability allows remote attackers to disclose bypass access IP restrictions on affected installations of Microsoft SharePoint Server. Authentication is required to exploit this vulnerability. The specific flaw exists within the SPWebRequest SafeCreate API. The issue results from a time-of-check-time-of-use when requesting ip addresses from DNS servers. An attacker can leverage this vulnerability to bypass IP restrictions when performing server-side request forgery attacks.

Affected Vendors:

Microsoft

Affected Products:

SharePoint Server

Vendor Response:

Microsoft has issued an update to correct this vulnerability. More details can be found at: <https://msrc.microsoft.com/update-guide/vulnerability/CVE-2022-21968&gt;