Supply chain · pip · High
Malicious pip package 'CalcBoxLite' beacons installer identity
Threat Engine Auto-Feed · data current as of 2026-08-28
The 'CalcBoxLite' package (version 1.0) on PyPI contains malicious code that exfiltrates user and hostname information upon installation and import. This critical severity supply-chain attack poses a significant risk by identifying systems and users interacting with the package, potentially leading to further targeted attacks.
- Package: pip / CalcBoxLite
- Affected versions: = 1.0
- Severity: critical
- Reach: unknown
- Exposure: 65/100 (High)
What happened — Malicious package
The 'CalcBoxLite' package, specifically version 1.0, was found to contain malicious code. This code is designed to collect system information, including the username and hostname, and transmit it to an external, unauthorized server. This exfiltration occurs automatically during the package installation process and again whenever the package is imported into a project.
How the attack works
This is a malicious package attack where a seemingly legitimate software component is compromised to perform unauthorized actions. In this instance, the package's setup script and initialization file are instrumented to gather identifying system details. These details are then sent to a remote collector, allowing attackers to identify systems that have installed or imported the malicious package. This type of attack focuses on reconnaissance, gathering intelligence about potential targets for subsequent malicious activities.
Who's exposed
Profiles most at risk
- Development teams using the pip ecosystem
- CI/CD pipelines that pull unpinned or latest versions of dependencies
- Organizations with internal package mirrors that may have synced the malicious version
- Any user or system that has installed or imported 'CalcBoxLite' version 1.0
Conditions that increase exposure
- Using unpinned dependencies in `requirements.txt` or similar configuration files
- Lack of dependency lockfiles (`Pipfile.lock`, `poetry.lock`) to ensure deterministic builds
- Automated build systems that do not vet new package versions before deployment
- Direct or transitive dependency on 'CalcBoxLite' version 1.0
Blast-radius scenarios
- An attacker gains knowledge of specific usernames and hostnames of systems that have interacted with the package, enabling targeted social engineering or infrastructure attacks.
- Compromised CI/CD runners or development environments reveal internal network details, increasing the blast radius for further exploitation.
- The exfiltrated data could be used to map an organization's development footprint, identifying potential entry points or high-value targets.
What to do (defensive)
Detect
- Scan dependency trees for 'CalcBoxLite' version 1.0.
- Monitor network traffic for outbound connections from build environments or applications to suspicious, unadvertised domains (e.g., `https://k4m2qhx7ptv9nzcr3bwe8syd6ljfa0gu1.oast.invalid/collect`).
- Review package installation logs for 'CalcBoxLite' version 1.0.
Contain
- Immediately block network access to the identified malicious collector domain from all internal systems and build environments.
- Quarantine or isolate any systems identified as having installed or imported 'CalcBoxLite' version 1.0.
- Remove 'CalcBoxLite' version 1.0 from all package repositories, caches, and mirrors.
Remediate
- Uninstall 'CalcBoxLite' version 1.0 from all affected systems and environments.
- Force a password reset for any user accounts whose usernames were potentially exfiltrated.
- Audit and update dependency management practices to use pinned versions and lockfiles for all third-party packages.
- Implement stricter egress filtering for build environments and development workstations to prevent unauthorized outbound connections.
Frontier verdict — High
Prioritize immediate detection and removal of 'CalcBoxLite' version 1.0 due to its critical severity and active exfiltration of system identity information.
Sources
For detection-engineering and awareness only · point-in-time · not security advice · sourced from the GitHub Advisory Database.