CVE-2024-53899: Command Injection Vulnerability in virtualenv Prior to 20.26.6
Summary
CVE-2024-53899: virtualenv before 20.26.6 allows command injection through the activation scripts for a virtual environment. Affects virtualenv versions < 20.26.6. Fixed in 20.26.6. How to fix ↓
Also tracked for
- virtualenv · Bitnami
- python-virtualenv · Debian:11
The same CVE-2024-53899 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.
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Background
virtualenv is a widely used Python tool that allows developers to create isolated environments for their projects. This isolation helps manage dependencies and avoid conflicts between packages. However, prior to version 20.26.6, virtualenv had a critical vulnerability that could allow attackers to execute arbitrary commands through improperly handled activation scripts.
Vulnerability Detail
The vulnerability arises from the way virtualenv handles magic template strings in its activation scripts. These strings are not quoted correctly, which can lead to command injection attacks. An attacker could exploit this flaw by crafting a malicious activation script that, when executed, runs arbitrary commands on the host system. This poses significant risks, including unauthorized access to sensitive data or system control.
How To Fix
Latest published version: 21.14.12 as of 22 Oct 2026
pip install --upgrade "virtualenv==21.14.12"Upgrading to it may include breaking changes; the version below is the minimum fixed release for this vulnerability.
If you need the minimum change
20.26.6
This is the first release that contains the fix.
pip install --upgrade "virtualenv==20.26.6"Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, users can avoid using activation scripts or ensure that no untrusted scripts are executed within their virtual environments until the package is updated.
Conclusion
The command injection vulnerability in virtualenv prior to version 20.26.6 poses a significant risk to users. It is crucial to update to the patched version to mitigate potential attacks. Users should also consider utilizing tools like Vulert for ongoing monitoring of vulnerabilities in their projects.
See every vulnerability recorded for virtualenv →
FAQ
The CVSS score of this vulnerability is 9.8, indicating a critical level of severity.
You can use Vulert's playground at Vulert Scanner to check if your application is affected by this vulnerability without any signup.
If exploited, this vulnerability could allow attackers to execute arbitrary commands, leading to data breaches or system compromise.
Yes, Vulert can monitor and alert you in real-time for open-source vulnerabilities in your software using just your Pipfile.lock.
If you cannot update the package right away, avoid executing untrusted activation scripts and consider using alternative methods to manage your Python environments.
References
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