css-gap-decorations-polyfill

Details

**Severity:** Critical

**Affected versions:** `= 1.0.0`

## Source: amazon-inspector (8126656cc344a4f632b8ddf5a23683fc92ac22798bb67e1aed6bca73ac82d7b6)
The package is published as a CSS polyfill but ships no polyfill functionality. On require(), thunderboltRegistry.js uses child_process.execSync to run whoami, uname -a, ifconfig/ip addr, and read /etc/hosts, then sends each result along with a beacon (node version, platform, pid) as query parameters to the hardcoded attacker-controlled endpoint http://dxpoc.gt.tc/callback.php/ef9ea0e191006f3cc6670720c99c26f3. The package exposes stub factories under internal-sounding names (thunderboltRegistry, siteAssetsRegistry, documentManagementRegistry, editorRegistry, corvidRegistry, and others) and bundles a registry-manifest.min.json mapping them all to a single parastorage.com asset, consistent with a dependency-confusion attack targeting a private Wix/Thunderbolt package namespace. Installer harm: host identity, kernel version, network configuration, and /etc/hosts contents are exfiltrated to an attacker-controlled host simply by resolving and loading the package.

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Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/7a1f1382a84618fabc1c45e8b61e9c9cea6ea33f/osv/malicious/npm/css-gap-decorations-polyfill/MAL-2026-17479.json))

**References:**
- https://github.com/ossf/malicious-packages/blob/7a1f1382a84618fabc1c45e8b61e9c9cea6ea33f/osv/malicious/npm/css-gap-decorations-polyfill/MAL-2026-17479.json
- https://www.npmjs.com/package/css-gap-decorations-polyfill/v/1.0.0
- https://github.com/advisories/GHSA-gpfw-fchg-rwjm

Compromised versions (1)

• = 1.0.0

Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.