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.
Attack Parameters
Attack Vector
Local
Requires local access
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products
mrubyc:mrubyc
References 3
https://github.com/mrubyc/mrubyc/blob/4261cf5e5ae5579e3110dab98a04b91c7d919429/…
disclosure@vulncheck.com
https://github.com/mrubyc/mrubyc/blob/release4.0.0/src/vm.c#L1537
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/mrubyc-through-4.0.0-null-pointer-derefere…
disclosure@vulncheck.com