CVE-2025-59684 is a vulnerability identified in DigiSign DigiSigner ONE version 1.0.4.60, involving DLL hijacking. DLL hijacking is a type of security flaw where an attacker places a malicious Dynamic Link Library (DLL) file in a location where the vulnerable application loads DLLs without proper path validation or integrity checks. When the application loads the malicious DLL instead of the legitimate one, the attacker can execute arbitrary code with the privileges of the application. DigiSigner ONE is a digital signature software used to sign documents electronically, and the presence of DLL hijacking in this software indicates that an attacker could potentially execute unauthorized code on systems running this version. The vulnerability details do not specify affected versions beyond 1.0.4.60, nor is there a patch currently available or known exploits in the wild. The lack of a CVSS score suggests that the vulnerability is newly published and not yet fully assessed. However, DLL hijacking vulnerabilities are generally considered serious due to their potential to allow code execution without requiring user interaction if the application is launched in an environment where the attacker can influence DLL search paths. This vulnerability could be exploited locally or via social engineering if an attacker can convince a user to open a malicious file or run the application in a compromised directory. The absence of detailed technical specifics limits the ability to fully assess exploitation complexity, but the nature of DLL hijacking implies moderate ease of exploitation in certain scenarios.

For European organizations, the impact of this vulnerability could be significant, especially for entities relying on DigiSign DigiSigner ONE for document signing workflows. Successful exploitation could lead to unauthorized code execution, potentially resulting in data breaches, manipulation of signed documents, or disruption of business processes. Confidentiality could be compromised if attackers gain access to sensitive documents or credentials stored or processed by the application. Integrity is at risk since attackers might alter signed documents or signatures, undermining trust in digital signatures. Availability could also be affected if attackers deploy malware or ransomware through this vector. Given the critical role of digital signatures in legal, financial, and governmental sectors across Europe, exploitation could have regulatory and reputational consequences. However, the impact is somewhat mitigated by the lack of known exploits and the need for specific conditions to exploit DLL hijacking, such as control over the DLL search path or user interaction.

To mitigate this vulnerability, European organizations should first verify if DigiSign DigiSigner ONE 1.0.4.60 is deployed within their environment. Since no patch is currently available, immediate steps include restricting write permissions on directories where the application loads DLLs to prevent unauthorized DLL placement. Implement application whitelisting and use endpoint protection solutions capable of detecting suspicious DLL loads. Organizations should also educate users about the risks of running applications from untrusted locations and avoid launching DigiSigner ONE from network shares or temporary directories. Monitoring for unusual process behavior or unexpected DLL loads can help detect exploitation attempts. Additionally, organizations should engage with DigiSign for updates or patches and plan to apply them promptly once released. Employing software restriction policies or Windows Defender Application Control to enforce trusted DLL loading paths can further reduce risk.