Critical Vulnerability in Python3 Packages on Alpine: CVE-2025-4516
Summary
ALPINE-CVE-2025-4516: There is an issue in CPython when using bytes.decode("unicode_escape", error="ignore|replace"). Affects python3 versions < 3.11.12-r1. Fixed in 3.11.12-r1. How to fix ↓
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Background
Python3 is a widely-used programming language known for its simplicity and versatility. It is utilized in various applications, from web development to data analysis. The Alpine Linux distribution, known for its lightweight and security-oriented design, includes Python3 as a core package. However, a vulnerability has been identified in the way Python3 handles certain byte decoding operations, potentially exposing applications to security risks.
Vulnerability Detail
The vulnerability arises from an issue in CPython when using the bytes.decode method with the 'unicode_escape' encoding and specific error handlers ('ignore' or 'replace'). This flaw can lead to unexpected behavior or security issues if not properly managed. The vulnerability is tracked under CVE-2025-4516 and affects multiple versions of Python3 across different Alpine Linux releases.
How To Fix
Minimum fixed version
3.11.12-r1
This is the first release that contains the fix.
sudo apk add --upgrade python3Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, avoid using the 'error' handler in the bytes.decode method. Instead, wrap the call in a try-except block to catch any DecodeError. Example code:
try: decoded_bytes = bytes.decode(your_bytes) except UnicodeDecodeError: # Handle the error appropriately decoded_bytes = '' # or any fallback action
Conclusion
CVE-2025-4516 presents a significant risk to applications using Python3 on Alpine Linux. It is crucial to update to the patched versions or implement the provided workaround to mitigate potential security threats.
See every vulnerability recorded for python3 →
FAQ
CVE-2025-4516 is a vulnerability in Python3 that affects how bytes are decoded using the 'unicode_escape' encoding with specific error handlers.
The vulnerability affects Python3 in Alpine Linux versions v3.18, v3.19, v3.20, v3.21, and v3.22.
You can use Vulert to monitor and alert for open-source vulnerabilities in your software by simply providing a manifest file like package-lock.json.
If an immediate update is not possible, implement the recommended workaround by avoiding the use of error handlers in the bytes.decode method.
Detailed information about CVE-2025-4516 can be found in the official CVE database and the Alpine Linux security advisories.
References
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