CVE-2025-13805 identifies a deserialization vulnerability in the NutzBoot framework, version 2.6.0-SNAPSHOT and earlier. The vulnerability resides in the getInputStream method within the LiteRpc-Serializer component, specifically in the file HttpServletRpcEndpoint.java. Deserialization flaws occur when untrusted data is processed by the application’s deserialization routines, potentially allowing attackers to execute arbitrary code or manipulate application logic. In this case, remote attackers can send crafted requests to the vulnerable endpoint to trigger unsafe deserialization. The attack vector is network-based (AV:N), with high attack complexity (AC:H), requiring no privileges (PR:N), no user interaction (UI:N), and no authentication. The impact is limited primarily to confidentiality (VC:L), with no direct integrity or availability impact reported. The CVSS 4.0 score of 6.3 reflects a medium severity due to the difficulty of exploitation and limited impact scope. Although a public exploit is available, no confirmed active exploitation in the wild has been reported. The vulnerability affects the NutzBoot framework, which is used in Java-based enterprise applications, particularly those leveraging the Nutzam ecosystem. The lack of patches at the time of reporting necessitates defensive measures to mitigate risk.

For European organizations, this vulnerability poses a moderate risk primarily to confidentiality, as exploitation could allow attackers to execute arbitrary code or access sensitive data through deserialization attacks. Organizations using NutzBoot in critical infrastructure, financial services, or government applications could face data breaches or unauthorized access. The medium complexity and lack of required privileges reduce the likelihood of widespread exploitation but do not eliminate risk, especially in targeted attacks. The availability of a public exploit increases the urgency for mitigation. Potential impacts include exposure of sensitive information, disruption of application logic, and potential footholds for further network compromise. Given the reliance on Java frameworks in many European enterprises, especially in Germany, France, and the UK, the vulnerability could affect a significant number of systems if not addressed promptly.

1. Monitor for and apply official patches or updates from the Nutzam project as soon as they become available. 2. Restrict network access to the affected LiteRpc-Serializer endpoints by implementing firewall rules or network segmentation to limit exposure. 3. Employ strict input validation and sanitization on all incoming data to the getInputStream function to prevent malicious payloads from triggering deserialization. 4. Consider implementing application-layer protections such as deserialization filters or using safer serialization libraries that enforce type whitelisting. 5. Conduct code reviews and security testing focused on deserialization logic within NutzBoot-based applications. 6. Deploy runtime application self-protection (RASP) or web application firewalls (WAF) with custom rules to detect and block suspicious deserialization attempts. 7. Increase monitoring and logging around the vulnerable component to detect potential exploitation attempts early. 8. Educate development and security teams about the risks of unsafe deserialization and best practices for secure coding in Java environments.