UNKNOWN READ vulnerability in mruby

mruby Updated 02 Oct 2025

Summary

06/03/2023

Disclosed on

MEDIUM

Severity

Yes i

Fix available

Medium

Severity

Not published

CVSS Score

OSV-2023-151: UNKNOWN READ in mrb_vm_find_method. Affects mruby versions >= 672495555bb741aefbde2f31a523f7ed8666d2c6, < 8d1192f8a28034b1931a41e8c55cd86715101d0c. Fixed in 8d1192f8a28034b1931a41e8c55cd86715101d0c. 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 embedded in other applications to provide scripting capabilities. This vulnerability affects the mrb_vm_find_method function in mruby, which is responsible for finding a method in the virtual machine. The vulnerability allows for an unknown read operation, leading to a crash. The issue was reported through the OSS-Fuzz project.

Vulnerability Detail

The UNKNOWN READ vulnerability in mrb_vm_find_method can potentially be exploited by an attacker to read sensitive information from the memory of the virtual machine. This could result in the disclosure of sensitive data or the execution of arbitrary code. The vulnerability is considered to have a medium severity level.

How To Fix

Minimum fixed version

8d1192f8a28034b1931a41e8c55cd86715101d0c

This is the first release that contains the fix.

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Workaround

There is no known workaround for this vulnerability at the moment.

Conclusion

The UNKNOWN READ vulnerability in mruby can potentially lead to the disclosure of sensitive information or the execution of arbitrary code. It is recommended to update the mruby package to the latest version to mitigate this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.

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