{"id":"MAL-2026-17548","summary":"Malicious code in css-ayucyz-polyfill (npm)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (d8c7540d3981f510255434529f76a2ed9a24b0783e7e8e3369b41f71b93ebd1a)\nOn 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.\n","modified":"2026-10-05T04:15:05.601060739Z","published":"2026-10-05T03:35:56Z","database_specific":{"malicious-packages-origins":[{"modified_time":"2026-10-05T03:35:56Z","sha256":"d8c7540d3981f510255434529f76a2ed9a24b0783e7e8e3369b41f71b93ebd1a","source":"amazon-inspector","versions":["1.0.0"],"id":"IN-MAL-2026-021016","import_time":"2026-10-05T03:57:38.936079948Z"}]},"references":[{"type":"PACKAGE","url":"https://www.npmjs.com/package/css-ayucyz-polyfill/v/1.0.0"}],"affected":[{"package":{"name":"css-ayucyz-polyfill","ecosystem":"npm","purl":"pkg:npm/css-ayucyz-polyfill"},"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."}],"indicators":{"evidence_files":[{"sha256":"a485cb48081ea590cab385a405886cfe6f30af7d415f30bc8d7937ace461b928","tlsh":"e87154a5b99df02065c33438cb7f4049b4bbc6672d6caee0744899b01f7985c01be6f8","path":"thunderboltRegistry.js"}],"package_integrity":[{"filename":"css-ayucyz-polyfill-1.0.0.tgz","hashes":{"sha512_sri":"sha512-sda4giLrVE4noopYdNNqcnETeBpm5sbJYOtwkqjE2Ik3ulbGrlzSWOZ3UGFd5k3kTPyaJrGACHySUg43jL0bVA==","sha1":"68637df5dcb71c369afd7780406885e777fc4b75"}}]},"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/npm/css-ayucyz-polyfill/MAL-2026-17548.json"}}],"schema_version":"1.9.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}