UNKNOWN READ vulnerability in mruby

mruby Updated 02 Oct 2025

Summary

01/07/2020

Disclosed on

MEDIUM

Severity

Yes i

Fix available

Medium

Severity

Not published

CVSS Score

OSV-2020-447: UNKNOWN READ in yyparse. Affects mruby versions >= ec6c8b2a3c5c499d8832ef82a2ad941cbac4a80a, < 264239f78fb9ec8047cf04b82f547fc41d65ab28. Fixed in 264239f78fb9ec8047cf04b82f547fc41d65ab28. How to fix ↓

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Background

mruby is an open-source embeddable scripting language that aims to be lightweight and easily integrated into various applications. It provides a simple and efficient way to add scripting capabilities to software projects. However, a vulnerability has been discovered in mruby that could potentially lead to unknown read access.

Vulnerability Detail

The vulnerability in mruby is related to the yyparse function, which is responsible for parsing input and generating an abstract syntax tree. The exact cause of the vulnerability is unknown, but it results in an unknown read access issue. This vulnerability could potentially be exploited by an attacker to read sensitive information from memory or cause a denial of service. The vulnerability has a medium severity rating.

How To Fix

Minimum fixed version

264239f78fb9ec8047cf04b82f547fc41d65ab28

This is the first release that contains the fix.

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Workaround

There is no specific workaround mentioned for this vulnerability.

Conclusion

In conclusion, the UNKNOWN READ vulnerability in mruby could potentially allow an attacker to read sensitive information or cause a denial of service. It is recommended to update mruby to the latest version that includes the fix for this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

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