CVE-2025-56571 is a Denial of Service (DoS) vulnerability found in Finance.js version 4.1.0, specifically affecting the IRR (Internal Rate of Return) function. The vulnerability arises from improper handling of the 'depth' parameter, which controls recursion or iteration limits within the IRR calculation algorithm. When an attacker supplies a crafted input that manipulates this parameter, it can cause the function to enter excessive recursive or iterative loops, leading to abnormally high CPU consumption. This excessive resource usage can cause the hosting application to stall, become unresponsive, or crash entirely. The vulnerability does not require authentication or user interaction to be exploited, as it is triggered by input parameters passed to the IRR function. No known exploits are currently reported in the wild, and no patches or fixes have been published at this time. The affected versions are not explicitly detailed beyond version 4.1.0, but it is implied that this version is vulnerable. The lack of a CVSS score indicates that the vulnerability is newly disclosed and has not yet undergone formal severity assessment. The core issue is a resource exhaustion attack vector that targets the availability aspect of affected systems using Finance.js for financial calculations involving IRR.

For European organizations, the impact of this vulnerability can be significant, particularly for financial institutions, fintech companies, accounting software providers, and any enterprise relying on Finance.js for financial computations. A successful exploitation could lead to service disruptions, application downtime, and degraded performance, affecting business continuity and customer trust. In environments where Finance.js is integrated into backend services or web applications that process financial data, the DoS could be leveraged by attackers to disrupt critical financial operations or cause cascading failures in dependent systems. Although the vulnerability does not directly compromise confidentiality or integrity, the availability impact could indirectly affect compliance with regulations such as GDPR, which mandates data availability and service reliability. Additionally, prolonged outages could result in financial losses and reputational damage. The absence of known exploits suggests a window of opportunity for organizations to proactively mitigate the risk before active attacks emerge.

To mitigate this vulnerability, European organizations should first identify all instances where Finance.js v4.1.0 is used, especially focusing on modules that perform IRR calculations. Until an official patch is released, organizations can implement input validation and sanitization to restrict the 'depth' parameter to safe, predefined limits, preventing excessive recursion or iteration. Employing runtime monitoring to detect abnormal CPU usage spikes during IRR function execution can help in early detection of exploitation attempts. Additionally, sandboxing or isolating the financial calculation components can limit the impact of potential DoS conditions on the broader application. Organizations should also consider upgrading to newer versions of Finance.js if and when patches addressing this vulnerability become available. Implementing rate limiting on API endpoints that invoke the IRR function can reduce the risk of automated exploitation. Finally, maintaining robust incident response plans and monitoring for unusual application behavior will enhance preparedness against potential attacks exploiting this vulnerability.