CVE-2025-53771 Scanner

Microsoft SharePoint Server is widely used by organizations to facilitate collaboration, document management, and storage of business-critical information. It allows users to create and manage intranet, extranet, and internet sites joined by a common set of templates and services. Due to its integration capabilities, it is often implemented in conjunction with other Microsoft Office products, amplifying its functionality. The platform is tailored for enterprise environments and used by IT professionals to streamline communication and collaboration. SharePoint Server's robust capabilities extend to workflow application development, which aids in automating business processes. Its deployment brings substantial benefits in terms of collaboration efficiency and information governance.

The improper authentication vulnerability in Microsoft SharePoint Server poses a significant risk as it may allow unauthorized actors to access sensitive systems and data. Identified as CVE-2025-53771, this security issue exploits inadequacies in the authentication process of SharePoint, enabling malefactors to impersonate legitimate users. This vulnerability could serve as an entry point for further attacks, making it critical to identify and mitigate. Combining this flaw with other vulnerabilities increases the risk of more severe exploits, such as remote code execution, potentially compromising entire systems. Maintaining the security and integrity of SharePoint deployments necessitates addressing such vulnerabilities promptly.

The CVE-2025-53771 vulnerability emerges from a flaw in SharePoint Server's handling of authentication requests, where a crafted POST request to /_layouts/15/ToolPane.aspx can be manipulated with a Referer header. By spoofing this header, attackers bypass authentication controls, gaining unauthorized access to privileged endpoints, such as administrative interfaces. This weakness exploits a gap in the mechanism that verifies published headers, thereby missing malicious forgeries. Armed with this access, attackers can proceed to execute commands or manipulate server functions undetected. This flaw forms part of a larger exploit chain and can work alongside other vulnerabilities such as CVE-2025-53770 to achieve more advanced actions.

If exploited, the improper authentication vulnerability in Microsoft SharePoint Server can lead to unauthorized access to sensitive information, potentially leading to data leakage and unauthorized data modification. It can allow attackers to compromise administrator accounts, enabling them to modify security settings, execute malicious scripts, or deploy further attacks within the network. The vulnerability poses a threat to the integrity and confidentiality of organizational data and can disrupt business operations by compromising the SharePoint environment. Preventive measures need to be undertaken to mitigate this risk as soon as possible.

REFERENCES

• https://nvd.nist.gov/vuln/detail/CVE-2025-53771
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-53771
• https://www.wiz.io/blog/sharepoint-vulnerabilities-cve-2025-53770-cve-2025-53771-everything-you-need-to-k
• https://orca.security/resources/blog/toolshell-sharepoint-exploit-cve-2025-53770-53771/
• https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/http/sharepoint_toolpane_rce.rb