Microsoft SharePoint Server provides a robust platform for sharing and managing data in a collaborative environment. However, vulnerabilities can lead to unauthorized data access, which is a serious security concern. In this article, we'll take a deep dive into CVE-2023-24954, a recently discovered information disclosure vulnerability affecting Microsoft SharePoint Server. We'll discuss the exploit details, provide code snippets, and highlight the original references to help you understand and protect your systems against this vulnerability.

Exploit Details

CVE-2023-24954 is an information disclosure vulnerability affecting Microsoft SharePoint Server. It is caused by insufficient validation of user-supplied data, which can lead to unauthorized access to sensitive information. An attacker can exploit this vulnerability by sending a specially crafted HTTP request, which could result in the disclosure of valuable application data or the data contained within the SharePoint Server environment.

Original CVE Reference: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-24954

Below is a simplistic example of an HTTP request that might exploit the CVE-2023-24954 vulnerability

GET /_api/web/lists/ExampleList HTTP/1.1
Host: vulnerable-sharepoint-site
User-Agent: Mozilla/5. (Windows NT 10.; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89..4389.114 Safari/537.36
Accept: application/json;odata=verbose
Cookie: FedAuth=INVALID_COOKIE_VALUE

In this example, the INVALID_COOKIE_VALUE represents an invalid or manipulated authentication cookie. An attacker sends this request to a vulnerable SharePoint Server, potentially resulting in the disclosure of sensitive information about the server's configuration, user credentials, and internal network environment.

Mitigation

Microsoft has acknowledged the vulnerability and released a security update to address the issue. The patch addresses the underlying problem by enhancing the validation of user-supplied data and ensuring proper access controls are in place. Applying this security update is crucial to protect your SharePoint environment from unauthorized information disclosure.

Patch Reference: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2023-24954

In addition to applying the patch, there are a few best practices you can follow to protect your SharePoint environment:

Regularly review and update your SharePoint Server configurations, policies, and permissions.

2. Monitor your SharePoint environment for signs of unauthorized access, such as suspicious log entries or failed login attempts.
3. Educate your users on the importance of security, including actions they can take to help protect sensitive information.

Conclusion

CVE-2023-24954 is an important information disclosure vulnerability affecting Microsoft SharePoint Server. Proper understanding and proactive mitigation measures can help you protect your organization's valuable data and maintain a secure collaborative environment. Be sure to keep up-to-date on security updates and follow best practices to ensure your SharePoint Server remains secure from threats like CVE-2023-24954.

Timeline

Published on: 05/09/2023 18:15:00 UTC
Last modified on: 05/16/2023 16:10:00 UTC