myreviews-corenpm
Advisory published Updated
myreviews-core is a confirmed malicious npm package (MAL-2026-10740) that opens a backdoor for remote access (malicious version 99.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in myreviews-core (npm)
What this malware does
package.json declares a postinstall lifecycle hook that runs node -e to issue an HTTPS GET to a hardcoded webhook.site collector URL, appending the installer's hostname (os.hostname()), OS username (os.userInfo().username), current working directory (process.cwd()), and a timestamp as query parameters. The request fires automatically on npm install with no opt-in and no relation to any documented package functionality. The version number (99.0.0) is consistent with a dependency-confusion lure intended to shadow an internal package name and beacon successful installs to the attacker.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for myreviews-core (version 99.0.0).
If you installed it — respond
myreviews-core 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 myreviews-core 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 myreviews-core-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.