Critical UNKNOWN WRITE Vulnerability in liblouis - Affects _lou_handlePassVariableAction
Summary
OSV-2025-262: UNKNOWN WRITE in _lou_handlePassVariableAction. Affects liblouis versions >= 60076cfb7da6c5c3da2dc74869045fffa9ab70c7. No fix is published. How to fix ↓
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Background
liblouis is an open-source library designed for translating text into braille and vice versa. It is widely used in assistive technologies to enhance accessibility for visually impaired users. The library supports multiple braille codes and provides a robust framework for text translation. However, it has been identified to have a critical vulnerability that could lead to unexpected behavior and potential data corruption.
Vulnerability Detail
The vulnerability is classified as an UNKNOWN WRITE occurring in the function _lou_handlePassVariableAction. This issue was reported through OSS-Fuzz, indicating that the library can crash due to improper handling of certain input actions. The crash state reveals that the function fails to manage memory correctly, which could lead to unauthorized memory writes, potentially allowing an attacker to exploit the system. This vulnerability is particularly concerning as it may lead to data loss or corruption, impacting the reliability of applications that depend on liblouis.
How To Fix
No fixed version is published for this vulnerability.
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Workaround
As a temporary workaround, users can avoid using the specific functionality that triggers the vulnerability until a patch is applied. This may involve modifying the application logic to bypass calls to _lou_handlePassVariableAction or similar functions that handle pass variable actions.
Conclusion
The UNKNOWN WRITE vulnerability in liblouis poses a significant risk to applications that utilize this library for text-to-braille translation. It is crucial for developers to update to the latest version to mitigate potential risks. Additionally, users can leverage tools like Vulert to monitor and alert for open-source vulnerabilities in their software.
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FAQ
The UNKNOWN WRITE vulnerability allows unauthorized memory writes, which can lead to application crashes or data corruption.
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The vulnerability could lead to application crashes, data loss, or corruption, affecting the reliability of software that relies on liblouis.
Yes, a patched version of liblouis is available. Users should update to the latest version to mitigate the risk.
If an immediate update is not possible, consider implementing a workaround by avoiding the use of the affected functions until a patch can be applied.
References
Related vulnerabilities
Recent vulnerabilities recorded for liblouis.
