Which versions of isb are malicious?

The following PyPI versions of isb are flagged malicious: 1.0.0, 1.2.1, 1.2.2. Treat any of these as compromised.

How do I remediate isb if I installed it?

isb 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.

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

If isb 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 isb part of a known attack campaign?

Yes — isb is associated with the 2026-02-isb, RLMA-2026-00433 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 isb across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for isb (3 malicious versions).

Malicious package

isbPyPI

Advisory published Feb 28, 2026Updated Mar 19, 2026

isb is a confirmed malicious PyPI package (MAL-2026-1090) that steals credentials and exfiltrates sensitive data (malicious versions 1.0.0, 1.2.1, 1.2.2). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in isb (PyPI)

MAL-2026-1090

Immediate action

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

pip uninstall isb

What this malware does

Starting the module initiates an infostealer with a Telegram bot and RAT-like functionality and hardcoded credentials. The code automatically adds itself to autostart, collects some credentials, and also awaits further commands. The code is capable of exfiltrating browser data, files, taking screenshots, recording audio and modifying some system configurations.

Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.

Campaign: 2026-02-isb

Reasons (based on the campaign):

infostealer
exfiltration-browser-data
exfiltration-credentials
peristence-autorun
rat
spyware-like
files-exfiltration
iritating-computer-activity

Malicious versions

3 flagged

1.0.01.2.11.2.2

Indicators of compromise (SHA-256)

93750cbddba7897fde1d31836971e11082ad2076012c7caf708980de45827840

72f47105de38891ff4fab09cee2a35d398d1d35978906afb939d9b7e16df2522

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for isb (3 malicious versions).
If you installed it — respond
isb 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 isb 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. isb on PyPI has been identified as a malicious package (versions 1.0.0, 1.2.1, 1.2.2 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

2026-02-isbRLMA-2026-00433

References

bad-packages.kam193.eu

Credits

Kamil Mańkowski (kam193) · reporter
ReversingLabs · finder

Detect & block this

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

Malware detection Runtime egress monitoring

Explore

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