CVE-2025-60455 identifies a critical unsafe deserialization vulnerability in Modular Max Serve software versions before 25.6. The vulnerability specifically arises when the "--experimental-enable-kvcache-agent" feature is enabled, which introduces insecure deserialization processes. Unsafe deserialization occurs when untrusted data is deserialized without proper validation, enabling attackers to craft malicious serialized objects that, when processed, can execute arbitrary code on the target system. This vulnerability allows remote attackers to potentially gain full control over affected systems by sending specially crafted payloads exploiting the deserialization flaw. The lack of a CVSS score indicates the vulnerability is newly published, with no public exploit code or detailed impact metrics yet available. However, the nature of unsafe deserialization vulnerabilities historically leads to high-impact remote code execution risks. Modular Max Serve is used in various enterprise environments, and the experimental feature in question may be enabled in development or production setups, increasing exposure. No authentication or user interaction is required, making exploitation straightforward if the vulnerable feature is enabled and accessible. No patches or mitigations are currently linked, emphasizing the need for immediate attention once updates are released. The vulnerability was reserved in late September 2025 and published in November 2025, indicating recent discovery and disclosure.

The impact of CVE-2025-60455 on European organizations can be severe. Successful exploitation results in arbitrary code execution, potentially allowing attackers to take full control of affected systems, leading to data breaches, service disruptions, or lateral movement within networks. Critical infrastructure, financial institutions, healthcare providers, and government agencies using Modular Max Serve with the vulnerable feature enabled face heightened risks. The ability to execute code remotely without authentication or user interaction increases the likelihood of automated attacks and wormable exploits. This could lead to significant confidentiality, integrity, and availability losses, including theft of sensitive data, deployment of ransomware, or sabotage of essential services. The absence of known exploits currently provides a window for proactive defense, but the risk of future exploitation remains high. European organizations with compliance obligations under GDPR and other regulations may face legal and financial consequences if breaches occur due to this vulnerability.

To mitigate CVE-2025-60455, organizations should immediately audit their Modular Max Serve deployments to determine if the "--experimental-enable-kvcache-agent" feature is enabled. If enabled and not essential, disable this feature to eliminate exposure. Monitor vendor communications closely for patches addressing this vulnerability and apply updates promptly once available. Implement network segmentation and strict access controls to limit exposure of vulnerable services to untrusted networks. Employ runtime application self-protection (RASP) or web application firewalls (WAFs) capable of detecting and blocking malicious serialized payloads. Conduct thorough logging and monitoring for unusual deserialization activity or unexpected process executions. Educate development and operations teams about the risks of unsafe deserialization and encourage secure coding practices. Finally, consider deploying intrusion detection systems (IDS) with signatures tailored to detect exploitation attempts targeting this vulnerability.