UNKNOWN WRITE in udiv in mruby

mruby Updated 02 Oct 2025

Summary

10/07/2022

Disclosed on

HIGH

Severity

Yes i

Fix available

High

Severity

Not published

CVSS Score

OSV-2022-562: UNKNOWN WRITE in udiv. Affects mruby versions >= 872020bb3d85ba4066ec19cfcad375e51fdf024b, < 8d349815309e374b545deb4d4202323c7bc5bd28. Fixed in 8d349815309e374b545deb4d4202323c7bc5bd28. 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 easily integrated into other software projects. The vulnerability in question affects the udiv function within the mruby codebase.

Vulnerability Detail

The vulnerability is categorized as an UNKNOWN WRITE crash type. It occurs in the udiv function, specifically in the mrb_bint_mod and int_mod functions. The exact cause and impact of the vulnerability are not specified in the provided information.

How To Fix

Minimum fixed version

8d349815309e374b545deb4d4202323c7bc5bd28

This is the first release that contains the fix.

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Workaround

No workaround is mentioned in the provided information.

Conclusion

In conclusion, the UNKNOWN WRITE vulnerability in udiv in mruby can be fixed by updating the package to a version that includes the fix. No workaround is mentioned, and further information can be found in the provided OSS-Fuzz report. For additional support on vulnerability remediation, you can reach out to DevNack.com.

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