Overview
The cybersecurity world is constantly evolving, and one of the latest vulnerabilities to surface is the CVE-2025-39503. This vulnerability is related to the deserialization of untrusted data in GoodLayers Goodlayers Hotel. Deserialization vulnerabilities are particularly dangerous because they can lead to remote code execution or even full system compromise. Given that GoodLayers Hotel is widely used in the hospitality industry, this vulnerability could potentially affect thousands of businesses worldwide.
Vulnerability Summary
CVE ID: CVE-2025-39503
Severity: Critical (9.8 CVSS Severity Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage
Affected Products
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Product | Affected Versions
GoodLayers Hotel | Up to and including 3.1.4
How the Exploit Works
The vulnerability exploits the deserialization of untrusted data. Deserialization is the process of converting a stream of bytes back into a copy of the original object. In this case, an attacker could exploit this vulnerability by sending a serialized object containing malicious code to a vulnerable system. The server would then deserialize the object, and if it does not properly validate or sanitize the incoming data, the malicious code could be executed.
Conceptual Example Code
Here is a conceptual example of how the vulnerability might be exploited:
POST /booking HTTP/1.1
Host: target.example.com
Content-Type: application/json
{ "bookingDetails": "eyJjbGFzcyI6ICJjb20uZ29vZGxheWVycy5ob3RlbC5Cb29raW5nRGV0YWlscyIsICJkYXRhIjogeyJjaGVja0luRGF0ZSI6ICIyMDI1LTAzLTAxIiwgImNoZWNrb3V0RGF0ZSI6ICIyMDI1LTAzLTAzIiwgImd1ZXN0Q291bnQiOiAyLCAicm9vbVR5cGUiOiAiRGVsdXhlIiwgInBheW1lbnRJbmZvIjogeyJjbGFzcyI6ICJjb20uc3VuLm1pc2MuVW5zYWZlIn0sICJtZXRob2ROYW1lIjogInJ1biIsICJhcmdzIjogWyIvc2Jpbi9iYXNoIiwgIi1jIiwgImNhdCAvZXRjL3Bhc3N3ZCJdfX0=" }In this example, the malicious payload is encoded in Base64. When decoded and deserialized by the server, it could potentially lead to the execution of a malicious shell command.
Mitigation Strategies
To mitigate the effects of this vulnerability, users are advised to apply the vendor patch as soon as it becomes available. As a temporary mitigation, users can also utilize a Web Application Firewall (WAF) or Intrusion Detection System (IDS) to detect and block attempts to exploit this vulnerability. Regularly updating and patching software is also a key strategy in minimizing the risk of any vulnerabilities.