About Remote Code Execution - Microsoft SharePoint (CVE-2026-58644) vulnerability. Information about this vulnerability was published on July 14 as part of the July Microsoft Patch Tuesday. The vulnerability in Microsoft SharePoint Server, caused by a deserialization flaw (CWE-502), allows an attacker with Site Owner privileges or higher to inject and remotely execute arbitrary code on the SharePoint server. This can result in full server compromise, including the exfiltration of corporate documents and data, their modification or deletion, compromise of credentials accessible to the server, and further lateral movement into the organization's internal infrastructure.

The authentication requirement, of course, makes exploitation of the vulnerability more difficult. However, an attacker could potentially leverage the previously disclosed EoP vulnerability CVE-2026-56164. At the same time, there is currently no confirmation that these vulnerabilities have been exploited together as part of a single attack chain.

👾 Microsoft experts flagged this vulnerability as being exploited in the wild on the day of Patch Tuesday. Two days later, on July 16, the vulnerability was added to the CISA KEV catalog. Details of the attacks are not yet known.

🛠 No public exploits have been observed so far.

⚙️ Updates are available for Microsoft SharePoint Server 2016, 2019, and Subscription Edition.