dolyame-ui-postcssconfignpm
dolyame-ui-postcssconfig is a confirmed malicious npm package (MAL-2026-13594) that executes malicious code on install (malicious version 35.8.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in dolyame-ui-postcssconfig (npm)
What this malware does
On require() of the package, index.js loads _polyfill.js and lib/telemetry.js, both of which fetch a platform-specific binary over HTTPS from one of four hardcoded Cloudflare Workers hostnames (oob-worker.cf102-baf.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev), with a DNS TXT-record fallback over sdk/ext/pkg/net subdomains of dl.wel1.ru. The fetched bytes are written to a disguised path under /var/tmp or the Windows temp directory, chmod 0755 is applied on POSIX, and the binary is spawned detached via /bin/sh -c or cmd.exe. Destination hostnames and sensitive API names (child_process, chmodSync, hostname) are assembled at runtime from split string fragments and joined arrays to defeat static string search. lib/telemetry.js embeds the same download-decode-chmod-spawn pattern inside ~3000 lines of fake 'Analytics SDK' framing, providing a second import-time execution path. The package name and declared purpose (postcss config for a UI library) do not match the shipped behavior.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for dolyame-ui-postcssconfig (version 35.8.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging dolyame-ui-postcssconfig across your stack and pipelines.
If you installed it — respond
Remove dolyame-ui-postcssconfig from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If dolyame-ui-postcssconfig was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks dolyame-ui-postcssconfig before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks dolyame-ui-postcssconfig-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.