CVE-2020-15866
CVSS v3
9.8
CRITICAL
EPSS Score
2.1 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
mruby through 2.1.2-rc has a heap-based buffer overflow in the mrb_yield_with_class function in vm.c because of incorrect VM stack handling. It can be triggered via the stack_copy function.
Technical details
- Published
- 2020-07-21
Frequently asked questions
What is CVE-2020-15866?
mruby through 2.1.2-rc has a heap-based buffer overflow in the mrb_yield_with_class function in vm.c because of incorrect VM stack handling. It can be triggered via the stack_copy function.
Is CVE-2020-15866 actively exploited?
Active exploitation of CVE-2020-15866 has not been confirmed. Its EPSS score was 2.1% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2020-15866?
CVE-2020-15866 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2020-15866 affecting your environment?
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