Description: An attacker exploits a known vulnerability in the underlying Sass compiler (e.g., Ruby Sass, Dart Sass) that is used to process Bourbon and application Sass files. This is a threat introduced by the dependency Bourbon has on a Sass compiler. By crafting malicious Sass code within the application's stylesheets that utilize Bourbon mixins, an attacker could trigger the Sass compiler vulnerability during the compilation process. This could lead to arbitrary code execution on the server performing the compilation or unauthorized access to the server's file system.
Impact: Critical. Successful exploitation of a Sass compiler vulnerability can result in complete server compromise, allowing for data breaches, malware installation, and denial of service.
Bourbon Component Affected: Indirectly affects Bourbon, as Bourbon's functionality relies on the Sass compilation process. The vulnerability resides in the Sass compiler dependency.
Risk Severity: High (depending on the specific Sass compiler vulnerability).
Mitigation Strategies:
- Maintain Updated Sass Compiler: Ensure the Sass compiler (Ruby Sass, Dart Sass, etc.) used with Bourbon is consistently updated to the latest stable version. This is crucial for patching known security vulnerabilities in the compiler itself.
- Monitor Sass Compiler Security Advisories: Regularly monitor security advisories and release notes for the specific Sass compiler in use. Promptly apply any security patches released by the Sass compiler maintainers.
- Secure Sass Compilation Environment: Implement security best practices for the environment where Sass compilation occurs. Limit file system access for the compilation process and restrict network access if possible.
Description: Developers may inadvertently misuse Bourbon mixins in a way that leads to CSS injection vulnerabilities. This occurs when Bourbon mixins are used to dynamically generate CSS properties based on unsanitized or improperly validated user input. An attacker can then inject malicious CSS code by providing crafted input that is incorporated into the generated CSS rules. This injected CSS can be used to deface the website, steal sensitive user information (e.g., through CSS data exfiltration techniques), or conduct clickjacking attacks.
Impact: High. Successful CSS injection can have a significant impact, potentially leading to user data compromise, website defacement, and reputation damage. In some scenarios, CSS injection can be leveraged for more advanced attacks.
Bourbon Component Affected: Bourbon mixins that are used for dynamic CSS generation, particularly those that manipulate properties like background-image, content, custom properties, or any property where user-controlled values might be incorporated.
Risk Severity: High.
Mitigation Strategies:
- Strict Input Sanitization: Always sanitize and rigorously validate all user input before using it to dynamically generate CSS, even when utilizing Bourbon mixins. Treat all user-provided data as potentially malicious.
- Secure CSS Generation Practices: Adhere to secure coding principles for CSS generation. Avoid directly embedding user input into CSS property values without proper encoding and validation. Employ output encoding techniques if necessary.
- Code Review for Dynamic CSS: Conduct thorough code reviews specifically focusing on areas where Bourbon mixins are used to generate CSS dynamically. Identify and remediate any potential CSS injection vulnerabilities.
- Content Security Policy (CSP): Implement a robust Content Security Policy (CSP) to mitigate the impact of successful CSS injection. CSP can restrict the actions that CSS can perform and limit the sources from which stylesheets can be loaded, reducing the potential damage from injected CSS.