cktool-corenpm
Malicious code in cktool-core (npm) Remove it immediately and rotate any exposed credentials.
What this malware does
cktool-core is the unscoped public-registry form of the private-scoped @apple/cktool.core package. Installers whose resolver misroutes the scoped name to the public npm registry receive this package instead of Apple's internal library. On install, postinstall.js generates and persists a per-installer UUID under XDG_CACHE_HOME (or ~/.cache) and POSTs it, along with version and timestamp fields, to a hardcoded external endpoint at npx-monitor-76056.azurewebsites.net/api/pingback. The behavior fires unconditionally via the declared postinstall lifecycle hook, so any misresolution results in attacker-controlled JavaScript executing on the installer's machine and an install beacon leaving to a non-vendor destination. The package.json description self-labels this as a dependency-confusion PoC, but the mechanism and installer impact are identical to a real dependency-confusion attack against Apple's private namespace.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for cktool-core (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging cktool-core across your stack and pipelines.
If you installed it — respond
cktool-core establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If cktool-core 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 cktool-core 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 cktool-core-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.