Which versions of midcorp are malicious?

The following npm versions of midcorp are flagged malicious: 1.1.9. Treat any of these as compromised.

How do I remediate midcorp if I installed it?

midcorp 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.

I already installed midcorp — how do I know if it already compromised me?

If midcorp 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.

Is midcorp part of a known attack campaign?

Yes — midcorp is associated with the IN-MAL-2026-004224 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 midcorp across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for midcorp (version 1.1.9).

Malicious package

midcorpnpm

Advisory published May 22, 2026Updated May 26, 2026

midcorp is a confirmed malicious npm package (MAL-2026-4610) that opens a backdoor for remote access (malicious version 1.1.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in midcorp (npm)

MAL-2026-4610

Immediate action

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

npm uninstall midcorp

What this malware does

The package masquerades as a pino-compatible logger (package.json keywords fast/logger/stream/json, exports module.exports.pino = middleware, lib filenames proto.js, redaction.js, multistream.js, transport.js, worker.js mirror pino's layout), but its actual runtime behavior is a remote-code-execution dropper. When a consumer requires midcorp and invokes the exported middleware() from index.js, a detached/unref'd child process spawns lib/caller.js, which performs axios.get against https://jsonkeeper.com/b/XRGF3 (an anonymous, mutable paste-bin host) and passes the returned data.cookie field to new Function.constructor('require', s)(require) — handing attacker-controlled JavaScript full Node.js require capabilities. The C2 URL is obfuscated as a base64 string disguised as a fake process.env.DEV_API_KEY default in lib/caller.js / lib/const.js (aHR0cHM6Ly9qc29ua2VlcGVyLmNvbS9iL1hSR0Yz → https://jsonkeeper.com/b/XRGF3), with a backup paste ID (4NAKK). The description field is unrelated boilerplate about vulnerability management. Three independent block signals (remote-eval of paste-bin content, pino impersonation cover, base64-hidden C2) leave no benign interpretation.

Malicious versions

1 flagged

1.1.9

Indicators of compromise (SHA-256)

bc6725ed066ed5aff9452bd82d278fd89c1548768124d8b89cb8e5a5e8c3b05a

Detection & response playbook

Backdoor / remote access

Find it
Search your lockfiles and build artifacts for midcorp (version 1.1.9).
If you installed it — respond
midcorp 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 midcorp 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

No. midcorp 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-2026-004224

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks midcorp-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.

Malware detection Runtime egress monitoring

Explore

All malware advisories How O3 detects malware Vulnerability database