CVE-2025-68429 is a vulnerability in Storybook, a widely used frontend development tool that allows developers to build UI components in isolation. The flaw arises from how Storybook handles environment variables defined in .env files during the static build process initiated by the 'storybook build' command. Specifically, when a .env file is present in the build directory, Storybook may inadvertently bundle these environment variables—including sensitive secrets such as API keys or credentials—into the generated static artifacts. Since these artifacts are often published to public or internal web servers, the bundled source code becomes accessible to anyone with access, leading to exposure of sensitive information to unauthorized actors. This issue affects Storybook versions starting from 7.0.0 up to but excluding versions 7.6.21, 8.6.15, 9.1.17, and 10.1.10. Notably, builds performed without .env files, such as those using CI environments that inject secrets via platform environment variables, are not vulnerable. The vulnerability does not impact the Storybook runtime environment ('storybook dev') or deployed applications that share the same repository. The root cause is an undocumented behavior in Storybook’s environment variable handling that was unintentionally exposing secrets. To remediate, users must upgrade to the fixed versions, audit their .env files for sensitive data, and rotate any exposed secrets. Additionally, projects that depended on the old behavior need to modify how environment variables are referenced, either by prefixing variables with 'STORYBOOK_' or specifying them explicitly in Storybook’s configuration, ensuring no sensitive secrets are included in the build artifacts.

For European organizations, this vulnerability poses a significant risk of sensitive information leakage, particularly for companies that use Storybook to build and publish UI component libraries publicly or internally. Exposure of environment variables can lead to unauthorized access to APIs, databases, or third-party services, potentially resulting in data breaches, service disruptions, or further exploitation. Organizations in sectors with strict data protection regulations, such as finance, healthcare, and government, may face compliance violations under GDPR if sensitive data is exposed. The risk is heightened for organizations that store critical secrets in .env files within the build directory and publish Storybook artifacts without proper controls. The vulnerability could facilitate lateral movement or privilege escalation if attackers leverage exposed credentials. Although no known exploits are reported in the wild yet, the ease of exploitation (no authentication or user interaction required) and the public availability of source bundles increase the likelihood of opportunistic attacks. The impact extends to the integrity and availability of services if attackers use exposed secrets to manipulate or disrupt operations.

European organizations should immediately upgrade all Storybook instances—both local development environments and CI/CD pipelines—to the patched versions 7.6.21, 8.6.15, 9.1.17, or 10.1.10. Conduct a thorough audit of all .env files used during Storybook builds to identify any sensitive secrets that may have been exposed. Rotate all potentially compromised keys, tokens, and credentials promptly. Modify build processes to avoid placing .env files containing secrets in the build directory or use CI environment variables instead, as these are not bundled into the build artifacts. For projects relying on the previous behavior, refactor environment variable usage by prefixing variables with 'STORYBOOK_' or explicitly defining them in Storybook’s configuration 'env' property, ensuring no sensitive information is included. Implement access controls on published Storybook artifacts, restricting public exposure where possible. Regularly review and monitor public repositories and artifact hosting sites for accidental leaks. Incorporate automated scanning tools in CI pipelines to detect inclusion of sensitive data in build outputs. Finally, educate development teams about secure environment variable management and the risks of bundling secrets in frontend artifacts.