Heap-buffer-overflow in udiv in mruby

mruby Updated 02 Oct 2025

Summary

25/07/2022

Disclosed on

MEDIUM

Severity

Yes i

Fix available

Medium

Severity

Not published

CVSS Score

OSV-2022-619: Heap-buffer-overflow in udiv. Affects mruby versions >= e04184185ab43b94980550e850d8813a415fa438, < e02e9ae434e462c2ff21f47c1210089951db562b. Fixed in e02e9ae434e462c2ff21f47c1210089951db562b. How to fix ↓

Free scan

Check if this vulnerability affects your application

Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.

Check my app free

No signup required · Results in about 60 seconds

Upload your dependency manifest or SBOM

Drag & drop your file here or Browse

Java Javascript PHP Python Go Rust Ruby Dart C/C++ Elixir CycloneDX SPDX

Upload a supported dependency manifest or SBOM. No installation or source-code access required.

See supported files and SBOM formats

SBOM sbom.json · bom.json · bom.xml · *.spdx.json · *.cdx.json · *.cdx.xml

Java pom.xml · gradle.lockfile · buildscript-gradle.lockfile

Javascript package-lock.json · yarn.lock · pnpm-lock.yaml

PHP composer.lock

Python poetry.lock · requirements.txt · Pipfile.lock

Go go.mod

Rust Cargo.lock

Ruby Gemfile.lock

Dart pubspec.lock

C/C++ conan.lock

Elixir mix.lock

Enter your work email to receive your report link.

Verify your email to view the full report and start 30 days of continuous monitoring. No credit card required.

Background

mruby is an open-source lightweight implementation of the Ruby programming language. It is designed to be embedded in other applications and provides a minimalistic and efficient runtime environment. The udiv function in mruby is responsible for performing unsigned integer division. However, a heap-buffer-overflow vulnerability has been discovered in this function.

Vulnerability Detail

The heap-buffer-overflow vulnerability in udiv can lead to a read of 4 bytes beyond the allocated buffer. This can result in a crash or potentially allow an attacker to execute arbitrary code. The vulnerability was reported through the OSS-Fuzz project, and the affected version of mruby can be found in the provided OSS-Fuzz report. The severity of this vulnerability is considered medium.

How To Fix

Minimum fixed version

e02e9ae434e462c2ff21f47c1210089951db562b

This is the first release that contains the fix.

Tip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →

Workaround

There is no specific workaround mentioned for this vulnerability. However, as a general best practice, it is always recommended to keep software up to date with the latest security patches and updates.

Conclusion

In conclusion, a heap-buffer-overflow vulnerability has been identified in the udiv function of mruby. This vulnerability can result in a crash or potential code execution. It is recommended to update mruby to the fixed version to address this issue. For further support on vulnerability remediation, please contact DevNack.com.

See every vulnerability recorded for mruby →