@workoscalifant/sudoku-termnpm
@workoscalifant/sudoku-term is a confirmed malicious npm package (MAL-2026-14040) that opens a backdoor for remote access (malicious versions 1.1.1, 1.1.2, 1.1.3…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @workoscalifant/sudoku-term (npm)
What this malware does
package.json declares a postinstall script that imports src/hint.js and calls nativeBinaryPath(), which execFileSyncs prebuilt/linux-x64/sudoku-hint with '--selftest' on every Linux x64 installer. The shipped Linux artifact is a ~34 MB Go-runtime executable (sha256 ac6b4523fbe02c79129e58bdc8d613ddfb3a786c23dd03fa4ab28ab38ff3e6e5) containing Go runtime symbols, chacha8, and /proc/self/cgroup / /proc/self/mountinfo references. The corresponding darwin-x64 artifact built from the same declared source (native/hint.c, ~200 lines of pure C) is only 12,968 bytes and contains the expected C solver strings ('SUDOKU-HINT %s ok', 'naked single', '_row_mask'). The Linux binary is roughly 2,600x larger than its macOS counterpart and cannot be produced by the shipped build recipe (gcc -static hint.c), yet it is deliberately crafted to respond to '--selftest' with 'SUDOKU-HINT' so src/hint.js accepts it as the legitimate helper. The README additionally claims a '26 KB' static-musl ELF that 'opens no sockets', contradicting the shipped bytes. The installer therefore executes opaque, unverifiable native code from an untrusted source at install time under the guise of a small C sudoku solver.
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 @workoscalifant/sudoku-term (7 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging @workoscalifant/sudoku-term across your stack and pipelines.
If you installed it — respond
@workoscalifant/sudoku-term 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 @workoscalifant/sudoku-term 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 @workoscalifant/sudoku-term 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 @workoscalifant/sudoku-term-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.