CVE-2025-49701: Microsoft SharePoint Server RCE Vulnerability

CVE-2025-49701 Overview

CVE-2025-49701 is an improper authorization vulnerability in Microsoft Office SharePoint Server. An authenticated attacker with low-privilege access can execute arbitrary code over the network against affected SharePoint deployments. The flaw maps to [CWE-285: Improper Authorization] and affects SharePoint Server Subscription Edition, SharePoint Server 2019, and SharePoint Server 2016. Microsoft addressed the issue in its security update guide. EPSS data places the vulnerability in the 83.1 percentile for exploitation probability, indicating elevated attacker interest in SharePoint server-side flaws.

Critical Impact

An authenticated network attacker can achieve arbitrary code execution on the SharePoint server, leading to full compromise of site content, configuration, and connected data sources.

Affected Products

• Microsoft SharePoint Server Subscription Edition
• Microsoft SharePoint Server 2019
• Microsoft SharePoint Server 2016 (Enterprise)

Discovery Timeline

• 2025-07-08 - CVE-2025-49701 published to NVD
• 2025-07-15 - Last updated in NVD database

Technical Details for CVE-2025-49701

Vulnerability Analysis

The vulnerability resides in the authorization logic of Microsoft SharePoint Server. SharePoint fails to properly verify that the requesting principal holds the rights required for a privileged server-side operation. An authenticated user with standard site access can therefore invoke functionality reserved for higher-privileged roles, and that functionality permits code execution within the SharePoint application context.

Exploitation requires network reachability to the SharePoint web front end and valid credentials, but no user interaction. The attack does not need to cross a security boundary at the client side, and the scope remains unchanged. A successful attacker gains read, write, and availability impact on the SharePoint farm, including hosted documents, lists, and configuration data.

Root Cause

The root cause is a missing or incorrect authorization check on a server-side code path. SharePoint trusts the authenticated session for an operation that should be gated by elevated role membership or specific permission levels. The condition aligns with [CWE-285] and is consistent with prior SharePoint server-side flaws where business-logic endpoints accept low-privilege identities for high-impact actions.

Attack Vector

An attacker authenticates to the SharePoint site with any valid account, then issues a crafted request to the vulnerable endpoint. Because the authorization check is improper, the server processes the request as if the caller were privileged and executes attacker-supplied logic. Microsoft has not published exploitation details, and no public proof-of-concept is listed in the references. Refer to the Microsoft Security Update CVE-2025-49701 advisory for vendor guidance.

Detection Methods for CVE-2025-49701

Indicators of Compromise

• Unexpected w3wp.exe child processes such as cmd.exe, powershell.exe, or csc.exe spawned from the SharePoint application pool identity.
• New or modified .aspx, .ashx, or .asmx files written under the SharePoint LAYOUTS, TEMPLATE, or site collection directories.
• Authenticated requests from low-privilege accounts to administrative or server-side handlers immediately followed by configuration changes.
• Outbound network connections initiated by the SharePoint worker process to non-corporate destinations.

Detection Strategies

• Hunt for process-lineage anomalies where the IIS worker process spawns scripting or compilation binaries on SharePoint servers.
• Correlate IIS logs for repeated POST requests to SharePoint handlers from a single authenticated user followed by privileged operations.
• Inspect the SharePoint Unified Logging Service (ULS) logs for authorization warnings and unexpected elevation events.
• Monitor file integrity on SharePoint hive directories to detect dropped web shells or modified layout pages.

Monitoring Recommendations

• Forward IIS, ULS, and Windows Security event logs from all SharePoint front-end servers to a centralized analytics platform.
• Alert on authenticated access from accounts that historically do not interact with the affected SharePoint endpoints.
• Baseline w3wp.exe child-process behavior and trigger on deviations such as shell or scripting host execution.

How to Mitigate CVE-2025-49701

Immediate Actions Required

• Apply the July 2025 Microsoft security update referenced in the Microsoft Security Update CVE-2025-49701 advisory to all affected SharePoint Server versions.
• Inventory SharePoint Server Subscription Edition, 2019, and 2016 deployments and prioritize internet-exposed farms first.
• Review SharePoint accounts and remove or disable any unused or stale low-privilege identities that could be abused for authenticated exploitation.

Patch Information

Microsoft published a fix in the Microsoft Security Response Center update guide for CVE-2025-49701. Administrators must install the cumulative update appropriate to their SharePoint Server build, run the SharePoint Products Configuration Wizard or PSConfig on each server in the farm, and confirm the patched build number across all web front ends and application servers.

Workarounds

• Restrict SharePoint authentication to known users by enforcing strong identity controls and removing anonymous or self-service access where business requirements allow.
• Place SharePoint behind a reverse proxy or web application firewall that enforces request inspection and rate limiting on administrative handlers.
• Segment SharePoint servers from general user networks and limit outbound connectivity from the SharePoint application pool identity.
• Increase ULS and IIS logging verbosity and forward logs to SIEM until patching is complete.

# Verify SharePoint farm build after patch installation
Get-SPFarm | Select-Object BuildVersion
Get-SPProduct -Local | Select-Object ProductName, PatchableUnitDisplayName, PatchLevel

# Run configuration wizard on each server after patch install
& "$env:CommonProgramFiles\Microsoft Shared\Web Server Extensions\16\BIN\PSConfig.exe" -cmd upgrade -inplace b2b -wait -force