Overview
The recently documented vulnerability CVE-2025-53690 is a severe cybersecurity risk affecting Sitecore Experience Manager (XM) and Experience Platform (XP). It exploits a weakness in the deserialization of untrusted data, enabling code injection. This vulnerability is particularly significant as it exposes users of affected versions of Sitecore platforms to potential system compromise and data leakage, undermining the integrity and confidentiality of their data.
The magnitude of the risk posed by this vulnerability is underscored by its Common Vulnerability Scoring System (CVSS) Severity Score of 9.0 – a high rating indicative of the severe level of potential damage. With the widespread use of Sitecore platforms, it’s crucial to understand the nature of this vulnerability and adopt recommended mitigation strategies promptly.
Vulnerability Summary
CVE ID: CVE-2025-53690
Severity: Critical (CVSS score: 9.0)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: System compromise, data leakage
Affected Products
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Product | Affected Versions
Sitecore Experience Manager (XM) | Up to and including 9.0
Sitecore Experience Platform (XP) | Up to and including 9.0
How the Exploit Works
The CVE-2025-53690 vulnerability takes advantage of a weakness in the deserialization process of untrusted data in Sitecore platforms. Deserialization is the process of converting data from a flat format into a structured one. If this process doesn’t properly validate or sanitize the input data, an attacker can inject harmful code that the application will unwittingly execute. This can lead to unauthorized access or control over system resources, which in turn can result in data breaches or system compromise.
Conceptual Example Code
Consider the following conceptual example of an HTTP request that exploits the vulnerability. Please note this is a hypothetical example and does not represent actual malicious code.
POST /Sitecore/Endpoint HTTP/1.1
Host: target.example.com
Content-Type: application/json
{ "serialized_object": "{ \"__type\": \"TypeConverter, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089\", \"AssemblyName\": \"System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089\", \"PropertyName\": \"AttackPayload\", \"IncompleteDeserialization\": true}" }In this example, the malicious payload is embedded in a serialized object. When the Sitecore server deserializes this object, it can trigger the execution of the malicious payload, causing potential harm to the system or data.
Recommended Mitigation
The recommended mitigation for CVE-2025-53690 is to apply the vendor-supplied patch as soon as possible. In the interim, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can offer a measure of temporary mitigation. However, these should not be considered long-term solutions as they do not address the root cause of the vulnerability. Regular patching and updating of software is a fundamental aspect of maintaining robust cybersecurity defenses.
