retracfixnpm
Advisory published Updated
retracfix is a confirmed malicious npm package (MAL-2026-12190) that steals credentials and exfiltrates sensitive data (malicious versions 1.0.0, 1.0.1, 1.0.3). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in retracfix (npm)
What this malware does
The npm package [email protected] ships with no documented functionality (empty description, no README, no source, no dependencies) and consists only of postinstall.js plus a single Windows PE at bin/ezfn.exe. package.json declares scripts.postinstall='node postinstall.js' and os=['win32']; postinstall.js enumerates bin/ for any.exe and unconditionally runs it via execFileSync on Windows installs. The bundled ezfn.exe is a.NET assembly whose metadata contains the type/member signatures of a remote-control agent and infostealer: ClientSocket / ConnectServer / BeginConnect / isConnected / ActivatePong for a C2 socket; SendBot / ChatID plus WebClient.DownloadString for a Telegram-bot exfil/command channel; ManagementObjectSearcher with the strings 'Antivirus' and 'Exclusion' for AV enumeration and Defender-exclusion registration; avicap32.dll for webcam capture; Microsoft.Win32 RegistryKey / CurrentUser Run-key persistence; WindowsIdentity/WindowsPrincipal privilege checks; SymmetricAlgorithm CreateEncryptor/Decryptor, WriteAllBytes, GetTempPath, InstallDir/InstallStr/LoggerPath; and a 'Spread' routine. The package name plus the binary name 'ezfn' (Easy Fortnite) fit a gaming-cheat lure. Running npm install retracfix on Windows drops and launches this binary, handing persistent remote control of the installer's host to the operator.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for retracfix (3 malicious versions).
If you installed it — respond
retracfix is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If retracfix 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 retracfix-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.