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-2020-739: UNKNOWN READ in str_decref. Affects mruby versions >= caba5fef274ab7df91b7247182ecbf2483b853b8, < 45aa5081e418423b47a32a06e0515406f63b64d2. Fixed in 45aa5081e418423b47a32a06e0515406f63b64d2. How to fix ↓

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Background

mruby is an open-source lightweight implementation of the Ruby programming language. It is designed to be embeddable and portable, making it suitable for use in resource-constrained environments. This vulnerability affects the mruby package and can lead to an UNKNOWN READ crash when certain conditions are met.

Vulnerability Detail

The vulnerability originates from a crash state in the str_decref function, which is part of the garbage collection process in mruby. When triggered, it can result in an UNKNOWN READ operation, potentially leading to a crash or other unexpected behavior. The impact of this vulnerability can vary depending on the specific usage of mruby in an application.

How To Fix

Minimum fixed version

45aa5081e418423b47a32a06e0515406f63b64d2

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 can lead to crashes or other unexpected behavior. It is recommended to update the mruby package to a version that includes the fix to address this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

See every vulnerability recorded for mruby →