Microsoft SharePoint Enterprise Server - Authentication Bypass (CVE-2025-49706)

CVE-2025-49706 is an improper authentication vulnerability in Microsoft SharePoint, affecting multiple server versions, that allows unauthorized attackers to perform spoofing attacks over a network. Exploiting this flaw could enable threat actors to impersonate legitimate users or services, potentially leading to unauthorized access or manipulation of sensitive information within SharePoint environments.

CrowdSec has been tracking this vulnerability and its exploits since 10th of December 2025.

According to CrowdSec data, while opportunistic exploitation dominates, a portion of threat actors trying to exploit CVE-2025-49706 apply basic targeting methods such as port or service detection. This indicates emerging patterns of selective targeting. Additionally, according to week-over-week analysis by CrowdSec, exploitation of CVE-2025-49706 is surging. Attack volumes are spiking well above historical norms, indicating widespread and escalating interest from threat actors. CVE-2025-49706 is currently experiencing high visibility and active exploitation across the internet.

Attackers exploit authentication bypass by sending crafted POST requests to the / _layouts/15/ToolPane.aspx endpoint with specific query parameters such as DisplayMode=Edit and a=/ToolPane.aspx, attempting unauthorized access to SharePoint server functions.