#Microsoft Office SharePoint

**Why is this advisory published to the Security Updates Guide Vulnerabilities tab instead of the Advisories tab?** We are publishing this advisory to the Security Update Guide's Vulnerabilities tab to document the related defense in depth security updates in the Deployments tab. Generally advisories do not contain security updates. However Microsoft Engineering elected to provide them to ensure customers could ensure they are protected. Please reference the Security Updates table or the Deployments tab to find the security update for related to your product.

**What privileges could be gained by an attacker who successfully exploited this vulnerability?** An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

**How could an attacker exploit the vulnerability?** In a network-based attack, an authenticated attacker, who has a minimum of Site Member permissions (PR:L), could execute code remotely on the SharePoint Server.

**According to the CVSS metric, privileges required is high (PR:H). What does that mean for this vulnerability?** An authenticated attacker with Site Owner permissions can use the vulnerability to inject arbitrary code and execute this code in the context of SharePoint Server.

**How could an attacker exploit the vulnerability?** An authenticated attacker with Site Owner permissions or higher could upload a specially crafted file to the targeted SharePoint Server and craft specialized API requests to trigger deserialization of file's parameters. This would enable the attacker to perform remote code execution in the context of the SharePoint Server.

**According to the CVSS metric, privileges required is high (PR:H). What does that mean for this vulnerability?** An authenticated attacker with Site Owner permissions can use the vulnerability to inject arbitrary code and execute this code in the context of SharePoint Server.

**According to the CVSS metric, privileges required is low (PR:H). What does that mean for this vulnerability?** An authenticated attacker with Site Owner permissions can use the vulnerability to inject arbitrary code and execute this code in the context of SharePoint Server.

**What type of information could be disclosed by this vulnerability?** The type of information that could be disclosed if an attacker successfully exploited this vulnerability is data inside the targeted website like IDs, tokens, cryptographic nonces, and other sensitive information.

**According to the CVSS metric, privileges required is low (PR:H). What does that mean for this vulnerability?** An authenticated attacker with Site Owner permissions can use the vulnerability to inject arbitrary code and execute this code in the context of SharePoint Server.

**How could an attacker exploit the vulnerability?** An authenticated attacker with Site Owner permissions or higher could upload a specially crafted file to the targeted SharePoint Server and craft specialized API requests to trigger deserialization of file's parameters. This would enable the attacker to perform remote code execution in the context of the SharePoint Server.