Overview
This report details a significant cybersecurity vulnerability, identified as CVE-2025-30384, which affects Microsoft Office SharePoint. This vulnerability arises from the deserialization of untrusted data, allowing unauthorized attackers to execute code locally. Given SharePoint’s widespread use in organizations for collaboration and document management, this vulnerability could potentially have serious implications, including system compromise or data leakage.
Vulnerability Summary
CVE ID: CVE-2025-30384
Severity: High (CVSS: 7.4)
Attack Vector: Network
Privileges Required: None
User Interaction: Required
Impact: Unauthorized code execution leading to potential system compromise or data leakage
Affected Products
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Product | Affected Versions
Microsoft Office SharePoint | All versions prior to security update
How the Exploit Works
An attacker exploiting this vulnerability would manipulate SharePoint’s data deserialization process. By injecting malicious code into serialized objects, an attacker can cause SharePoint to deserialize untrusted data, leading to the execution of arbitrary code within the security context of the SharePoint server. Such an exploit does not require any special privileges but does necessitate user interaction, such as opening a crafted document or visiting a malicious webpage.
Conceptual Example Code
Below is a simplified, conceptual example of a malicious HTTP request exploiting this vulnerability:
POST /SharePoint-endpoint HTTP/1.1
Host: target.example.com
Content-Type: application/json
{
"serialized_object": "eyJjbGFzc25hbWUiOiJjb20uZXhhbXBsZS5FeGFtcGxlQ2xhc3MiLCJ2YWx1ZSI6InNvbWUgdmFsdWUifQ==",
"malicious_code": "base64_encoded_malicious_code_here"
}In this example, the attacker sends a serialized object embedded with malicious code. The SharePoint server, upon deserializing the object, inadvertently executes the code, thus exploiting the vulnerability.
Mitigation Guidance
Users are advised to apply the latest security patch provided by Microsoft for Office SharePoint, which addresses this vulnerability. In the absence of a patch, deploying a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can offer temporary mitigation by blocking or alerting on suspicious behavior related to deserialization.