@react-case/optionnpm
Advisory published Updated
@react-case/option is a confirmed malicious npm package (MAL-2026-10626) that executes malicious code on install (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @react-case/option (npm)
What this malware does
The package's main entrypoint (index.js) is heavily obfuscated with a string-array + RC4-style decoder that reconstructs all API names and the target URL at runtime. On module load it requires fs, os, path, crypto, and child_process, performs an HTTP GET against the runtime-reconstructed remote host, splits the response on ':', decrypts the parts with createDecipheriv using a hardcoded key/IV, writes the resulting bytes to a file under os.homedir(), and executes that file via child_process with cwd set to the user's home directory and windowsHide:true. The package ships no README, has an empty description and empty author metadata, and there is no legitimate library functionality — the only effect of requiring it is fetch-decrypt-write-exec of attacker-controlled code on the installer's machine.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for @react-case/option (version 1.0.0).
If you installed it — respond
Remove @react-case/option from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If @react-case/option was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks @react-case/option-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.