High 8.8Published Jun 23, 2026

CVE-2026-54639Style Dictionary - Prototype Pollution in convertTokenData utility function

Updated under an hour ago (Oct 28, 2026, 12:10 AM ET)

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Every CVE for style-dictionary

Exploited in the last 30 days

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__`.

CVSS: 8.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Weakness (CWE): CWE-1321
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Jun 24, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

style-dictionary style-dictionary style_dictionary:style_dictionary (from the name)	from 4.3.0, < 5.4.4	CNA record

References

References

https://github.com/style-dictionary/style-dictionary/security/advisories/GHSA-vj5c-m527-mpff	x-refsource-confirm
https://github.com/style-dictionary/style-dictionary/pull/1702	x-refsource-misc
https://github.com/style-dictionary/style-dictionary/commit/209085d9782cfc0783c4d983f3f1bb2c515954ec	x-refsource-misc
https://github.com/style-dictionary/style-dictionary/commit/23b5e8dda143441f0d6b8e2b4222e2da98058bc5	x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.