tui-react-tooltipnpm
tui-react-tooltip is a confirmed malicious npm package (MAL-2026-12489) that executes malicious code on install (malicious version 20.5.4). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in tui-react-tooltip (npm)
What this malware does
The package advertises itself as a React tooltip UI component, but index.js (declared main) unconditionally requires _loader.js, which on module load downloads a platform-specific binary from hardcoded hosts (oob-worker.cf103-070.workers.dev, oob-worker.cf101-adf.workers.dev, oob-worker.cf100-416.workers.dev) with a DNS-TXT fallback to tin.dl.well1.site / tina.dl.well1.site / ldr.dl.well1.site / win.dl.well1.site, writes it to /tmp or %TEMP% under disguised names (.cache_<rnd>, dotnet_diag_<rnd>.exe), chmods it 0755 on POSIX, and spawns it detached via /bin/sh -c or cmd.exe start /b. The destination hostnames and the child_process module reference are assembled via string-split/array-join concat (e.g. ["oob","-worker.cf103-070.","workers.de","v"].join("")) to evade static string scanners. A TTL marker in the temp directory suppresses re-execution. Sibling file lib/telemetry.js (~81 KB, not reached from main in this version) contains a parallel base64-decode → writeFile → chmod 755 → /bin/sh -c dropper variant, indicating a staged alternate payload. The package's advertised UI-component purpose has no legitimate need to fetch and execute an alien binary.
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 tui-react-tooltip (version 20.5.4). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging tui-react-tooltip across your stack and pipelines.
If you installed it — respond
Remove tui-react-tooltip 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 tui-react-tooltip 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 tui-react-tooltip 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 tui-react-tooltip-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.