Which versions of @postex/common are malicious?

The following npm versions of @postex/common are flagged malicious: 99.9.1. Treat any of these as compromised.

How do I remediate @postex/common if I installed it?

Remove @postex/common 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.

I already installed @postex/common — how do I know if it already compromised me?

If @postex/common 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 @postex/common part of a known attack campaign?

Yes — @postex/common is associated with the IN-MAL-2026-021691 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 @postex/common across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for @postex/common (version 99.9.1).

Malicious package

@postex/commonnpm

Advisory published Oct 25, 2026Updated Oct 25, 2026

@postex/common is a confirmed malicious npm package (MAL-2026-18285) that executes malicious code on install (malicious version 99.9.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in @postex/common (npm)

MAL-2026-18285

Immediate action

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

npm uninstall @postex/common

What this malware does

@postex/[email protected] ships an inert index.js (module.exports = {}) and declares a single dependency ltidisafe whose value is a bare HTTPS tarball URL (https://ltidi.storage.googleapis.com/depenconf/ltidisafe-3.9.5.tgz) rather than a registry version range. On npm install, npm fetches whatever bytes that URL returns, installs the resulting package, and executes any lifecycle scripts it contains, with no registry-mediated integrity, signature, or version pinning. The host (a user-controlled Google Cloud Storage bucket) is unrelated to any npm scope or published repository for this package, and the content served there can change at any time without any change to this manifest. The implausibly high version (99.9.1) combined with a hollow stub and an off-registry source is consistent with a dependency-confusion / smuggling lure whose only install-time effect is resolving to attacker-controlled code.

Malicious versions

1 flagged

99.9.1

Indicators of compromise (SHA-256)

2fb98ad3575267cc8fbf617fe6a17000ed10df97d39710f4b7aaddf7225598d7

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for @postex/common (version 99.9.1).
If you installed it — respond
Remove @postex/common 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 @postex/common 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. @postex/common on npm has been identified as a malicious package (version 99.9.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-021691

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks @postex/common-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

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