chai-solidity-testkitnpm
chai-solidity-testkit is a confirmed malicious npm package (MAL-2026-5907) that typosquats a legitimate package to trick installs (malicious versions 1.6.1, 1.6.4). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in chai-solidity-testkit (npm)
What this malware does
The package masquerades as a Web3/Solidity testing toolkit but its shipped source is an unrelated stream-pipeline library plus a hidden payload runner. The default export chaiPlugin (src/index.js) calls runChain, which spawns node src/utils/swap.js as a detached, unref'd child process. swap.js issues an HTTPS GET to https://jsonkeeper.com/b/CS0FU, takes the response's data.config string, and executes it via new Function.constructor('require', s) invoked with the real require — granting the remote operator full Node.js capabilities (filesystem, network, child_process, env) on the installer's machine. The remote endpoint is author-mutable (a public paste host), so the executed code can change at any time without a package update. The detach+unref pattern lets the payload outlive the calling process. The package name and description impersonate the chai/solidity testing namespace, and the only reason axios is declared as a dependency is to drive the remote fetch in swap.js.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
TyposquatFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for chai-solidity-testkit (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging chai-solidity-testkit across your stack and pipelines.
If you installed it — respond
chai-solidity-testkit is a typosquat — you almost certainly intended a legitimately-named package. Remove chai-solidity-testkit, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If chai-solidity-testkit 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 chai-solidity-testkit 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 chai-solidity-testkit-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.