CVE-2025-59042
PyInstaller bundles a Python application and all its dependencies into a single package.
Overview
CVE-2025-59042 is a known-severity vulnerability. It was published on September 9, 2025.
Technical description
PyInstaller bundles a Python application and all its dependencies into a single package. Due to a special entry being appended to `sys.path` during the bootstrap process of a PyInstaller-frozen application, and due to the bootstrap script attempting to load an optional module for bytecode decryption while this entry is still present in `sys.path`, an application built with PyInstaller < 6.0.0 may be tricked by an unprivileged attacker into executing arbitrary python code when **all** of the following conditions are met. First, the application is built with PyInstaller < 6.0.0; both onedir and onefile mode are affected. Second, the optional bytecode encryption code feature was not enabled during the application build. Third, the attacker can create files/directories in the same directory where the executable is located. Fourth, the filesystem supports creation of files/directories that contain `?` in their name (i.e., non-Windows systems). Fifth, the attacker is able to determine the of
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
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Frequently asked questions
What is CVE-2025-59042?
CVE-2025-59042 is a known-severity vulnerability. It was published on September 9, 2025.
How severe is CVE-2025-59042?
CVSS score information is not yet available for this vulnerability. Check back as the CVE record is updated by NVD analysts.
How do I fix or remediate CVE-2025-59042?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2025-59042?
CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2025-59042 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.