CVE-2018-10191: Debian Linux
Critical severity, CVSS 9.8. EPSS: 2.6% chance of exploitation in the next 30 days.
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.
Affected products
Published 2018-04-17. Last modified 2026-06-17.