Malicious code in css-ayucyz-polyfill (npm)
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (d8c7540d3981f510255434529f76a2ed9a24b0783e7e8e3369b41f71b93ebd1a) On require, thunderboltRegistry.js runs an IIFE that acquires child_process via multiple fallbacks and executes shell commands (id, whoami, uname -a, ifconfig/ip addr, cat /etc/hosts), then GETs the collected output along with the hostname, platform and Node version to the hardcoded plain-HTTP endpoint http://dxpoc.gt.tc/callback.php/bb8968d0f67000433bf7005dd5ad2d1f. One of the beacons is self-labeled beacon=rce-poc. The package presents itself as a CSS polyfill and exposes modules named thunderboltRegistry, siteAssetsRegistry, editorRegistry and corvidRegistry — internal Wix Thunderbolt names — behind a Proxy returning no-op functions, with registry-manifest.min.json pointing fake entries at a static.parastorage.com URL, so a consumer that resolves this package in place of the real Wix internals loads the exfiltration IIFE while the facade silently returns no-ops.
MAL-2026-17548
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: osv:MAL-2026-17548
css-ayucyz-polyfill
Source reference: /affected/0/package/name
- Affected versions
- 1.0.0
Source reference:
/affected/0/versions - Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"package": {
"name": "css-ayucyz-polyfill",
"purl": "pkg:npm/css-ayucyz-polyfill",
"ecosystem": "npm"
},
"versions": [
"1.0.0"
],
"database_specific": {
"cwes": [
{
"name": "Embedded Malicious Code",
"cweId": "CWE-506",
"description": "The product contains code that appears to be malicious in nature."
}
],
"source": "https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/css-ayucyz-polyfill/MAL-2026-17548.json",
"indicators": {
"evidence_files": [
{
"path": "thunderboltRegistry.js",
"tlsh": "e87154a5b99df02065c33438cb7f4049b4bbc6672d6caee0744899b01f7985c01be6f8",
"sha256": "a485cb48081ea590cab385a405886cfe6f30af7d415f30bc8d7937ace461b928"
}
],
"package_integrity": [
{
"hashes": {
"sha1": "68637df5dcb71c369afd7780406885e777fc4b75",
"sha512_sri": "sha512-sda4giLrVE4noopYdNNqcnETeBpm5sbJYOtwkqjE2Ik3ulbGrlzSWOZ3UGFd5k3kTPyaJrGACHySUg43jL0bVA=="
},
"filename": "css-ayucyz-polyfill-1.0.0.tgz"
}
]
}
}
}
]Publisher severity
No explicit severity was provided.
- Event
- #83617 · Revision 1
- Added to Heist Feed
- Publisher date