CVE-2026-25141 is a critical code injection vulnerability identified in orval, a tool that generates type-safe JavaScript (TypeScript) clients from OpenAPI v3 or Swagger v2 specifications. The vulnerability exists in versions starting from 7.19.0 up to but not including 7.21.0, and from 8.0.0 up to but not including 8.2.0, where an incomplete fix for a previous vulnerability (CVE-2026-23947) was implemented. The core issue lies in the insufficient sanitization of input strings used in code generation. While the jsStringEscape function correctly escapes common characters such as single and double quotes, it fails to escape certain special characters like square brackets ([]), parentheses (()), exclamation marks (!), and plus signs (+). An attacker can exploit this by leveraging a technique known as JSFuck, which encodes JavaScript code using only six characters, none of which are alphanumeric or quotes. This allows bypassing the sanitization logic and injecting arbitrary JavaScript code into the generated client code. The vulnerability does not require any authentication or user interaction, and the attack surface is network-exposed, making it highly exploitable remotely. Successful exploitation can lead to arbitrary code execution in the context where the generated client code runs, potentially compromising confidentiality, integrity, and availability of affected systems. The vulnerability has a CVSS 4.0 base score of 9.3, indicating critical severity with high impact on confidentiality, integrity, and availability, and low attack complexity. Versions 7.21.0 and 8.2.0 of orval contain updated fixes that properly address this injection vector by improving the sanitization logic. No known exploits are reported in the wild as of the publication date, but the ease of exploitation and critical impact warrant immediate attention.

For European organizations, this vulnerability poses a significant risk, especially those that incorporate orval-generated clients into their software development lifecycle or production environments. Exploitation can lead to arbitrary JavaScript execution, which may result in data theft, unauthorized access, or disruption of services. Industries with high reliance on JavaScript tooling, such as financial services, healthcare, and critical infrastructure, face heightened risks due to the potential for cascading effects from compromised client applications. The vulnerability's network-exploitable nature means attackers can remotely target vulnerable systems without prior access, increasing the threat landscape. Additionally, compromised client code can be propagated through supply chains, affecting multiple organizations downstream. The lack of required authentication or user interaction further amplifies the risk, making automated exploitation feasible. European data protection regulations, such as GDPR, impose strict requirements on data security; a breach resulting from this vulnerability could lead to regulatory penalties and reputational damage. Organizations using orval in continuous integration/continuous deployment (CI/CD) pipelines must be vigilant to prevent injection of malicious code into their software products.

To mitigate CVE-2026-25141, European organizations should immediately upgrade orval to versions 7.21.0 or 8.2.0, which contain the updated fix addressing the code injection vulnerability. It is critical to audit all generated client code for suspicious patterns or injection attempts, especially if older versions were used recently. Incorporate static code analysis tools capable of detecting code injection risks in generated code. Review and harden CI/CD pipelines to ensure that only sanitized and verified OpenAPI specifications are processed by orval. Implement strict input validation and sanitization on all OpenAPI/Swagger specifications before client generation. Where possible, isolate orval-generated clients in sandboxed environments to limit the impact of potential exploitation. Monitor network traffic and application logs for anomalous JavaScript execution or injection indicators. Educate development teams about the risks of code injection and the importance of using updated tooling. Finally, maintain an inventory of software dependencies to quickly identify and remediate vulnerable versions of orval in use.