CVE-2026-86547

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.

CVSS v3 6.2 MEDIUM

6.2^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.5 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/mrubyc/mrubyc/blob/4261cf5e5ae5579e3110dab98a04b91c7d919429/src/vm.c#L1534
https://github.com/mrubyc/mrubyc/blob/release4.0.0/src/vm.c#L1537
https://www.vulncheck.com/advisories/mrubyc-through-4.0.0-null-pointer-dereference-via-op-enter

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-09 10:22

Updated : 2026-09-10 19:58

NVD link : CVE-2026-86547

Mitre link : CVE-2026-86547

CVE.ORG link : CVE-2026-86547

JSON object : View

Products Affected

No product.

CWE

CWE-476

NULL Pointer Dereference

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