MalwarePublished 8 Jun 2026Updated 9 Jul 2026

rlask (PyPI) · Malicious Code

Affects rlaskSource GCVE Database

Malicious package : remove rlask and rotate any secrets on hosts that installed it.

Data as of 11 Jul 2026, 09:43 UTC

Classification

Malicious package

Published to PyPI · OSV MAL-2026-5303

What to do

Remove rlask from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.

Affected software

Product	Affected	Fixed in
PyPIrlask	Affected 3.1.3 – 3.1.7 5 affected builds	Fixed in–

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Description

--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (89a034f9ba4356799034d728884eccecf5c53779d85280556419cda38e671a30) The package name 'rlask' is a single-character edit of the popular 'flask' package. METADATA declares 'Maintainer-email: Pallets <contact@palletsprojects.com>', and entry_points.txt registers 'flask=flask.cli:main' rather than an rlask-specific entry — indicating the distribution is a verbatim repackaging of Flask 3.1.x source while falsely advertising Pallets maintainership. The exported API (Flask, Blueprint, Config, request, session, etc.) mirrors Flask's surface. No exfiltration, install-time hooks, subprocess execution, credential reads, or outbound network I/O were observed in the shipped code. The risk is name confusion plus forged maintainer identity: a developer who mistypes 'pip install flask' as 'pip install rlask' receives a package that shadows the real Flask, controlled by an author who is not Pallets and could push a malicious update at any time. Routing to human review per the typosquat handling discipline — name-confusion judgments and impersonated-maintainer attributions should be confirmed by a human before publication. ## Source: kam193 (baacd735e23c83962845507427fa53c89bdc2e8e0456dbbce6f00a91bf4fe002) Typosquatting package published from a compromised account with an obfuscated infostealer. The infostealer is a heavily obfuscated JavaScript code executed using Bun runtime on Python startup. It collectes all kinds of sensitive data, including API keys, credentials to package repositories, cryptocurrency assets, password manager data. Infostealer actively queries online services to collect additional secrets as well as attempts to gain persistence and spread further by publishing infected packages using collected credentials. Data are exfiltrated likely using Github. The code seems to threaten to wipe the user's data if it detects invalid GitHub tokens. Cleanup should be done with caution. It seems to be related to the recent Mini Shai Hulud campaign. --- Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers. Campaign: 2026-06-compr-woodpecker Reasons (based on the campaign): - compromised-package - exfiltration-env-variables - exfiltration-cloud-tokens - exfiltration-credentials - abuses-pth - obfuscation - infostealer - The package contains code to detect if it is running in a sandbox environment. - exfiltration-crypto - files-exfiltration - destructive-actions

Impact

Users who mistakenly install 'rlask' instead of 'flask' risk having sensitive credentials and secrets stolen, including API keys, cloud tokens, cryptocurrency assets, and password manager data. The malware can exfiltrate stolen data, maintain persistence, and propagate by publishing additional infected packages. It also has destructive capabilities that may lead to data loss if triggered. This can result in severe compromise of developer environments, cloud accounts, and personal data security.

Defensive guidance

The primary mitigation is to avoid installing 'rlask' and verify package names carefully before installation. Users should only install the legitimate 'flask' package from PyPI. Review and revoke any credentials or tokens that may have been exposed if 'rlask' was installed. Conduct thorough cleanup of affected environments with caution due to destructive payloads. Monitor for suspicious package activity and consider using tools that detect typosquatting and malicious packages.

Summary

The 'rlask' package is a malicious typosquatting package on PyPI that mimics the legitimate 'flask' package by copying its source code and forging maintainer identity. Unlike the genuine Flask package, 'rlask' includes heavily obfuscated JavaScript infostealer code executed through the Bun runtime at Python startup. This infostealer collects a wide range of sensitive information such as API keys, package repository credentials, cryptocurrency assets, and password manager data. It actively queries online services to gather additional secrets and attempts to maintain persistence and spread by publishing infected packages using compromised credentials. Data exfiltration is likely conducted via GitHub. The malware also has destructive functionality that may wipe user data if invalid GitHub tokens are detected. This threat is linked to the Mini Shai Hulud campaign and represents a significant risk of credential compromise and data loss.

References

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What to do

Affected software

Description

AI analysisMachine-generated, updated 9 Jul 2026, 09:51 UTC

Technical details

References

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