Typosquatting Attack Targets Python Developers with Malicious Package
Severity: High (Score: 64.5)
Sources: Gbhackers, www.netskope.com, snyk.io, thehackernews.com
Published: · Updated:
Keywords: package, python, malicious, mimics, parsimonious, parser, sophisticated
Severity indicators: ics
Summary
A typosquatting attack was launched against Python developers via a malicious package named 'parsimonius' on PyPI, designed to mimic the legitimate 'parsimonious' library. By altering a single character, attackers exploited developer trust, leading to 2,474 downloads before the package was removed. The rogue package featured a version number higher than the legitimate one, encouraging inadvertent installations. It contained a dual-purpose payload that blended in with legitimate functionality while deploying a Telegram-based backdoor for command-and-control communication. The backdoor targeted sensitive data such as database credentials and API keys, allowing attackers to gain unauthorized access to systems. This incident highlights vulnerabilities in automated dependency resolution systems used in modern development workflows. The malicious package's rapid adoption underscores the risks associated with supply chain compromises in open-source software. Key Points: • A malicious package named 'parsimonius' mimicked the legitimate 'parsimonious' library on PyPI. • The attack resulted in 2,474 downloads before the package was removed by PyPI administrators. • The package deployed a Telegram-based backdoor to facilitate remote access and data theft.
Detailed Analysis
**Impact** Python developers and organizations relying on the parsimonious parsing library are affected, with 2,474 downloads recorded before removal. The attack potentially compromises development environments across enterprises, open-source projects, and individual machines globally. Stolen data includes environment variables (.env files) containing database credentials, API keys, configuration secrets, and bot authentication tokens, enabling lateral movement, unauthorized API access, and production environment breaches. **Technical Details** The attack used a typosquatting package named “parsimonius” on PyPI, differing by one character from the legitimate parsimonious library, with a deliberately higher version number to trigger automated updates. The malicious package included legitimate parsing functionality to evade detection and deployed a Telegram-based backdoor for command-and-control communication. The backdoor allowed remote command execution, file system access, and real-time surveillance. The package SHA1 hash is a01c2a21f24db63cb01a67016519aebeca438089. No CVEs exploited were mentioned. **Recommended Response** Scan artifact repositories, CI/CD pipelines, and local environments for the SHA1 hash a01c2a21f24db63cb01a67016519aebeca438089 and remove any instances found. Implement package signature verification and maintain allowlists of approved dependencies. Deploy typosquatting detection tools such as Snyk or Phylum to prevent installation of malicious packages. Monitor for unusual Telegram API traffic indicative of C2 communications.
Source articles (5)
- Malicious Python Package Mimics Parsimonious Parser — Gbhackers · 2026-06-05
A sophisticated typosquatting attack targeting Python developers through a malicious package named “parsimonius” on the Python Package Index (PyPI). The rogue package was engineered to impersonate the… - Malicious Python Package Mimics Parsimonious Parser — Gbhackers · 2026-06-05
A sophisticated typosquatting attack targeting Python developers through a malicious package named “parsimonius” on the Python Package Index (PyPI). The rogue package was engineered to impersonate the… - Malicious Packages Found To Be Typo Squatting In Pypi — snyk.io · 2026-06-05
Two malicious packages were removed from the Python Package Index ( PyPI ) this week. These packages, jeIlyfish (a misspelling of the package jellyfish only noticeable when using certain fonts) and py… - Python Developers Warned Of Trojanized — thehackernews.com · 2026-06-05
- Telegram Abused As C2 Channel For New Golang Backdoor — www.netskope.com · 2026-06-05
Timeline
- 2026-06-05 — Malicious package discovered on PyPI: The 'parsimonius' package was found to be a typosquatting attempt, leading to 2,474 downloads before removal.
Related entities
- Malware (Attack Type)
- Supply Chain Attack (Attack Type)
- CWE-200 - Exposure of Sensitive Information (Cwe)
- Brickstorm (Malware)
- Jeilyfish (Malware)
- Parsimonius (Malware)
- T1036 - Masquerading (Mitre Attack)
- T1059 - Command and Scripting Interpreter (Mitre Attack)
- T1071 - Application Layer Protocol (Mitre Attack)
- T1195 - Supply Chain Compromise (Mitre Attack)
- Aiohttp (Platform)
- BeautifulSoup (Platform)
- PyPI (Platform)
- Telegram (Platform)
- Python (Tool)
- Requests (Tool)
- TensorFlow (Tool)
- a01c2a21f24db63cb01a67016519aebeca438089 (Sha1)