dolyame-ui-storybook-menunpm
dolyame-ui-storybook-menu is a confirmed malicious npm package (MAL-2026-13186) that executes malicious code on install (malicious version 35.5.6). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in dolyame-ui-storybook-menu (npm)
What this malware does
The package's main entry index.js unconditionally requires _ext.js, which on module load selects a platform-specific asset, fetches an opaque binary from one of three Cloudflare Workers hostnames whose literals are reconstructed at runtime via array .join("") splitting (oob-worker.cf100-416.workers.dev and two siblings) with a DNS TXT fallback under *.dl.wel1.ru, writes the bytes to a temp path disguised as a system file (.cache_<hex> on POSIX, dotnet_diag_<hex>.exe on Windows), chmod 0755 on POSIX, and spawns it detached via /bin/sh -c... & or cmd.exe /c start /b. A stamp file named .analytics_state and gating on DISABLE_TELEMETRY / ANALYTICS_OPT_OUT / DO_NOT_TRACK, plus a sibling lib/telemetry.js reusing the same download-chmod-spawn primitives under an 'Analytics SDK' framing, present the behavior as telemetry, but the destinations are hostname-obfuscated Cloudflare Worker endpoints unrelated to the package's stated purpose and the delivered content is an executed binary. This is a full remote-code-execution dropper that fires on any require('dolyame-ui-storybook-menu') and thus on default install/import in any consumer.
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-storybook-menu (version 35.5.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging dolyame-ui-storybook-menu across your stack and pipelines.
If you installed it — respond
Remove dolyame-ui-storybook-menu 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-storybook-menu 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-storybook-menu 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-storybook-menu-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.