Which versions of express-mongo-santi are malicious?

The following npm versions of express-mongo-santi are flagged malicious: 1.1.9. Treat any of these as compromised.

How do I remediate express-mongo-santi if I installed it?

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

I already installed express-mongo-santi — how do I know if it already compromised me?

If express-mongo-santi 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 express-mongo-santi part of a known attack campaign?

Yes — express-mongo-santi is associated with the IN-MAL-2026-014634 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 express-mongo-santi 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 express-mongo-santi (version 1.1.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging express-mongo-santi across your stack and pipelines.

Malicious package

express-mongo-santinpm

express-mongo-santi is a confirmed malicious npm package (MAL-2026-12377) that typosquats a legitimate package to trick installs (malicious version 1.1.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in express-mongo-santi (npm)

MAL-2026-12377

Immediate action

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

npm uninstall express-mongo-santi

What this malware does

The package's main file index.js is a heavily obfuscated bundle (obfuscator.io-style rotated string array with base64+RC4 decoders) whose only purpose is a remote-fetch-and-execute pipeline that fires when the module is require()'d. On load it pulls in os, fs, path, crypto, child_process, and https, assembles a hardcoded IPv4 destination from four numeric octets concatenated at runtime, issues an HTTPS GET to that host, splits the response on ':' into an IV and ciphertext, derives an AES key with crypto.scryptSync, decrypts the body with createDecipheriv, writes the plaintext to a file under os.homedir(), and spawns it via child_process with cwd set to the home directory. Module, method, and destination strings are all reconstructed at runtime through the decoders, and an uncaughtException handler suppresses errors. The package name is also a typosquat of express-mongo-sanitize. Installing or importing this package results in arbitrary attacker-controlled code executing on the installer's machine under the installer's user identity.

Malicious versions

1 flagged

1.1.9

Indicators of compromise (SHA-256)

85c97cf70eead9dda2069dc9da7e4a780f7c69953714ad050566c0e94a343e33

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 express-mongo-santi (version 1.1.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging express-mongo-santi across your stack and pipelines.
If you installed it — respond
express-mongo-santi is a typosquat — you almost certainly intended a legitimately-named package. Remove express-mongo-santi, 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 express-mongo-santi 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 express-mongo-santi 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. express-mongo-santi on npm has been identified as a malicious package (version 1.1.9 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-014634

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks express-mongo-santi-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

Explore

All malware advisories How O3 detects malware Vulnerability database