CVE-2018-10191

Name: CVE-2018-10191
Creator: NVD / NIST
Published: 2018-04-17T21:29:00.233+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 2.58%

Last modified Jun 17, 2026

CVE-2018-10191 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. In versions of mruby up to and including 1.4.0, an integer overflow exists in src/vm.c::mrb_vm_exec() when handling OP_GETUPVAR in the presence of deep scope nesting, resulting in a use-after-free. An attacker that can cause Ruby code to be run can use this to possibly execute arbitrary code.. EPSS estimates a 2.58% chance of exploitation in the next 30 days.

Description

In versions of mruby up to and including 1.4.0, an integer overflow exists in src/vm.c::mrb_vm_exec() when handling OP_GETUPVAR in the presence of deep scope nesting, resulting in a use-after-free. An attacker that can cause Ruby code to be run can use this to possibly execute arbitrary code.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

2.58%

83.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-190

Affected Software

Vendor	Product	Versions
Mruby	Mruby	<= 1.4.0
Debian	Debian Linux	9.0

References

https://github.com/mruby/mruby/commit/1905091634a6a2925c911484434448e568330626Patch, Third Party Advisory
https://github.com/mruby/mruby/issues/3995Exploit, Issue Tracking, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/05/msg00006.htmlMailing List, Third Party Advisory
https://github.com/mruby/mruby/commit/1905091634a6a2925c911484434448e568330626Patch, Third Party Advisory
https://github.com/mruby/mruby/issues/3995Exploit, Issue Tracking, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/05/msg00006.htmlMailing List, Third Party Advisory

Timeline

Published: Apr 17, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-10191?

How severe is CVE-2018-10191?

CVE-2018-10191 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 2.58% probability of exploitation in the next 30 days.

How do I fix CVE-2018-10191?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-10191?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST