dolyame-ui-overridestylesnpm
dolyame-ui-overridestyles is a confirmed malicious npm package (MAL-2026-13591) 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-overridestyles (npm)
What this malware does
On require() of the package, _compat.js invokes a setup() routine that downloads a platform-specific binary from Cloudflare Workers hosts assembled by joining split string fragments (oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev), with a DNS-TXT chunked-base64 fallback across sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The fetched bytes are written to a cover-named file under TMP or /var/tmp (e.g., dotnet_diag_.exe,.cache_), chmod 0755 on Unix, and spawned detached via /bin/sh -c or cmd.exe. A second dropper path in lib/telemetry.js (loaded via the package main) reconstructs an executable from base64 buffers, chmods 0755, and spawns via /bin/sh. Hostnames, the child_process require, and chmodSync are constructed by concatenation to evade static scanners. No hash or signature verification is performed on the downloaded payloads. The purpose is inconsistent with the package's presented name (a UI style-override library).
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-overridestyles (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-overridestyles across your stack and pipelines.
If you installed it — respond
Remove dolyame-ui-overridestyles 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-overridestyles 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-overridestyles 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-overridestyles-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.