CVE-2026-54639
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk3th percentile — higher than 3% of all known CVEs
Summary
Style Dictionary, a build system for creating cross-platform styles, has a prototype pollution vulnerability from version 4.3.0 to 5.4.4. Users are at risk with direct or indirect usage of the API, especially in NodeJS server applications.
Risk Assessment
The risk is high when style-dictionary is used in NodeJS server applications, moderate in web applications, and low in cases where the user maintains the token data.
Recommendation
It is recommended to upgrade to version 5.4.4 or sanitize token data before use. Also, check the token data object recursively for any object keys that include `__proto__`.
Original NVD description (English source)
Style Dictionary, a build system for creating cross-platform styles, has a prototype pollution vulnerability starting in version 4.3.0 and prior to version 5.4.4. Impact users have: direct usage of `convertTokenData(tokens, { output: 'object' });`; indirect usage, via using Expand API; and/or indirect usage via SD's transform lifecycle. Impact is high for this when style-dictionary is used as an integration in a NodeJS server application. Impact is moderate for when style-dictionary is used as an integration in a Web application. Impact is low for most common cases where the user of style-dictionary also maintains the tokens, and access is limited via read/write access to the repository/workflows where it is used. A patch has been published in version `5.4.4`. The only known workaround is to sanitize token data first. Whether using DTCG format or old Style Dictionary format, check the token data object recursively for any object keys that include `__proto__`.