typedecodenpm
typedecode is a confirmed malicious npm package (MAL-2026-6476) that typosquats a legitimate package to trick installs (malicious versions 1.0.1, 1.0.2, 1.0.3). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in typedecode (npm)
What this malware does
On require('typedecode') / import 'typedecode', the bundled dist/index.cjs and dist/index.js execute an obfuscated import-time payload. A bootstrap.js IIFE exposes require and module on global, deobfuscates two large strings through a custom permutation (YWG), constructs a function via the Function constructor (AQq(erE, YWG(fvm))), invokes it on a second decoded payload to produce XZs, then calls XZs(7942) and brands global._V = 'A6-Shadow-15'. The deliberate placement of require/module on globals before the IIFE allows the decoded code to dynamically load arbitrary Node modules (fs, http, child_process, etc.) without any static reference. The package's API surface and inline comments are copied verbatim from the legitimate decoders package by nvie (including the email-regex comment and the pojo detection comment), and the README API (object, array, optional, string, number, email, url, uuid, decode/verify/value, formatInline, formatShort) duplicates that library — an impersonation lure to drive installs of the hidden loader. Author is the placeholder-style chavanetsanastasia-netizen.
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
TyposquatFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for typedecode (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging typedecode across your stack and pipelines.
If you installed it — respond
typedecode is a typosquat — you almost certainly intended a legitimately-named package. Remove typedecode, 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 typedecode 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 typedecode 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 typedecode-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.