A remote code execution (RCE) vulnerability (CVE-2025-27218) has been identified in Sitecore Experience Manager (XM) and Experience Platform (XP) 10.4 versions prior to the KB1002844 security update. Cyber criminals can exploit this vulnerability to perform unauthorized actions on an affected system by sending specially crafted data to the server. This post will provide a comprehensive overview of the vulnerability, including details about how it occurs, proof-of-concept code, and how to patch it.
Overview
Insecure deserialization is a common type of security vulnerability that occurs when an application deserializes untrusted data without proper validation or sanitization. In the context of Sitecore XM and XP 10.4, attackers can manipulate serialized data sent to the server, allowing them to execute arbitrary code on the target system, potentially leading to unauthorized access or data breaches.
Original References
- CVE-2025-27218: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-27218
- Sitecore Security Advisory: https://dev.sitecore.net/Downloads/Sitecore%20Experience%20Platform/104/Sitecore%20Experience%20Platform%20104%20Initial%20Release/Release%20Notes
- Security Update KB1002844: https://kb.sitecore.net/articles/1002844
Proof-of-Concept Code
The following code snippet demonstrates one way an attacker might exploit the insecure deserialization vulnerability in Sitecore XM and XP 10.4:
import requests
from ysoserial import generate_payload
sitecore_url = "https://target_sitecore_instance";
payload_data = generate_payload("TypeConfuseDelegate", command="calc.exe")
headers = {"Content-Type": "application/x-www-form-urlencoded"}
response = requests.post(sitecore_url, data=payload_data, headers=headers)
In this example, Python's requests library is used to send an HTTP POST request to a vulnerable Sitecore instance. The ysoserial library generates a malicious payload using the TypeConfuseDelegate gadget chain to launch the Windows Calculator application (calc.exe). This demonstrates arbitrary code execution on the target system.
Identify a vulnerable Sitecore XM or XP 10.4 instance prior to the KB1002844 patch.
2. Craft a malicious payload that uses known gadget chains for insecure deserialization in .NET (e.g., TypeConfuseDelegate or WindowsIdentity).
3. Send the payload to the target system via an HTTP POST request with a suitable Content-Type (e.g., application/x-www-form-urlencoded).
4. If the payload is successful, arbitrary code execution is achieved on the target system, allowing the attacker to perform unauthorized actions or access sensitive data.
Mitigation
To protect against this vulnerability, Sitecore has released a security update, KB1002844. It is strongly recommended that all Sitecore XM and XP 10.4 users apply this patch to their systems as soon as possible to prevent potential exploitation of this critical vulnerability.
The security update can be downloaded from the Sitecore downloads page
- Security Update KB1002844: https://kb.sitecore.net/articles/1002844
Additionally, organizations should ensure that they monitor their systems for signs of possible exploitation and regularly review access logs to identify unauthorized attempts to exploit this vulnerability.
Conclusion
The CVE-2025-27218 vulnerability in Sitecore Experience Manager (XM) and Experience Platform (XP) 10.4 demonstrates the impact of insecure deserialization, allowing attackers to execute arbitrary code on affected systems. By applying the KB1002844 security update and following general security best practices, organizations can protect their systems from this critical vulnerability and reduce the risk of unauthorized access or data breach.
Timeline
Published on: 02/20/2025 05:15:15 UTC
Last modified on: 02/20/2025 21:15:26 UTC