CVE-2025-49704: 
vulnerability analysis and mitigation

A critical vulnerability identified as CVE-2025-49704 affects Microsoft Office SharePoint, allowing an authorized attacker to execute code over a network through improper control of code generation (code injection). The vulnerability was initially disclosed on July 8, 2025, and has been actively exploited in the wild (NVD, CISA). The vulnerability affects multiple versions of SharePoint Server, including SharePoint Server 2019 and 2016.

The vulnerability has been assigned a CVSS v3.1 Base Score of 8.8 (HIGH) with the vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. The vulnerability is classified under CWE-94 (Improper Control of Generation of Code) and allows code injection attacks. The vulnerability specifically affects the authentication mechanism in SharePoint, enabling attackers to execute remote code through network-based attacks (NVD).

The exploitation of this vulnerability can lead to full system compromise, allowing attackers to execute arbitrary code on affected SharePoint servers. Successful exploitation enables threat actors to gain unauthorized access to SharePoint content, including file systems and internal configurations, and execute malicious code over the network (Microsoft Security).

Microsoft has released comprehensive security updates for all supported versions of SharePoint Server. Organizations should immediately apply these updates and implement several critical mitigations: use supported versions of SharePoint Server, enable and configure Antimalware Scan Interface (AMSI), deploy Microsoft Defender Antivirus, rotate SharePoint Server ASP.NET machine keys, and restart IIS on all SharePoint servers. For organizations unable to immediately patch, it is recommended to disconnect affected servers from the internet (MSRC Blog).

CISA has added this vulnerability to their Known Exploited Vulnerabilities (KEV) catalog, requiring federal agencies to take immediate action. The security community has responded with heightened concern due to the active exploitation by multiple threat actors and the potential for ransomware deployment (CISA).