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CVE-2026-86547 Details

ANALYZED

This CVE record has been analyzed and enriched by NVDAPI.com as an independent party.

Description

mrubyc through 4.0.0 contains a null pointer dereference vulnerability in the op_enter() handler in src/vm.c when processing untrusted bytecode. Attackers can craft malicious .mrb bytecode files with OP_ENTER instructions at the top level to crash the embedding application and cause denial of service.

Metrics

CVSS 3.x Severity and Vector Strings:

VolerionCVSS-B:6.2 MEDIUMVector:CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CNA: [email protected]CVSS-B:6.2 MEDIUMVector:CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

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URL	Source(s)	Tag(s)
https://github.com/mrubyc/mrubyc/blob/4261cf5e5ae5579e3110dab98a04b91c7d919429/src/vm.c#L1534	[email protected]	Source CodeVendor
https://github.com/mrubyc/mrubyc/blob/release4.0.0/src/vm.c#L1537	[email protected]	Source CodeVendor
https://www.vulncheck.com/advisories/mrubyc-through-4.0.0-null-pointer-dereference-via-op-enter	[email protected]	Advisory

Weakness Enumeration

CWE-ID	CWE Name	Source
CWE-476	NULL Pointer Dereference	[email protected]

Affected Products

Product	Versions
mrubyc	>= 2.0, <= 4.0.0
CPE No CPEs found in CPE dictionary for this product. Remediation No remediation found in references.

Change History

2 change records found show changes

Date	Action	Recorded By
Sep 9, 2026	CVE Modified	CISA-ADP
Sep 9, 2026	New CVE Received	[email protected]