Advisory Details

May 13th, 2021

Microsoft SharePoint Server-Side Control Interpretation Conflict Remote Code Execution Vulnerability

ZDI-21-574
ZDI-CAN-12949

CVE ID CVE-2021-28474
CVSS SCORE 8.8, (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
AFFECTED VENDORS Microsoft
AFFECTED PRODUCTS SharePoint
VULNERABILITY DETAILS

This vulnerability allows remote attackers to execute arbitrary code on affected installations of Microsoft SharePoint. Authentication is required to exploit this vulnerability.

The specific flaw exists within the handling of server-side controls. By specifying a control using a non-canonical string, an unsafe server-side control can be instantiated. An attacker can leverage this vulnerability to execute code in the context of the service account.

ADDITIONAL DETAILS Microsoft has issued an update to correct this vulnerability. More details can be found at:
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-28474
DISCLOSURE TIMELINE
  • 2021-02-08 - Vulnerability reported to vendor
  • 2021-05-13 - Coordinated public release of advisory
CREDIT Anonymous
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