Mitsubishi Electric MELSEC-Q Series PLCs Resource Exhaustion

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

• mitsubishielectric q03udecpu firmwareup to 20101 inclusive
• mitsubishielectric q03udvcpu firmwareup to 20081 inclusive
• mitsubishielectric q04udehcpu firmwareup to 20101 inclusive
• mitsubishielectric q04udpvcpu firmwareup to 20081 inclusive
• mitsubishielectric q04udvcpu firmwareup to 20081 inclusive
• mitsubishielectric q06udehcpu firmwareup to 20101 inclusive
• mitsubishielectric q06udpvcpu firmwareup to 20081 inclusive
• mitsubishielectric q06udvcpu firmwareup to 20081 inclusive
• mitsubishielectric q100udehcpu firmwareup to 20101 inclusive
• mitsubishielectric q10udehcpu firmwareup to 20101 inclusive
• mitsubishielectric q13udehcpu firmwareup to 20101 inclusive
• mitsubishielectric q13udpvcpu firmwareup to 20081 inclusive
• mitsubishielectric q13udvcpu firmwareup to 20081 inclusive
• mitsubishielectric q20udehcpu firmwareup to 20101 inclusive
• mitsubishielectric q26udehcpu firmwareup to 20101 inclusive
• mitsubishielectric q26udpvcpu firmwareup to 20081 inclusive
• mitsubishielectric q26udvcpu firmwareup to 20081 inclusive
• mitsubishielectric q50udehcpu firmwareup to 20101 inclusive

Versions reported by the vendor

Affected version ranges reported by the assigning authority (icscert). Independent of NVD's CPE analysis and usually ahead of it.

• Mitsubishi Electric Q03/04/06/13/26UDVCPU

  • up to and including serial number 20081affected

• Mitsubishi Electric Q03UDECPU, Q04/06/10/13/20/26/50/100UDEHCPU

  • up to and including serial number 20101affected

• Mitsubishi Electric Q04/06/13/26UDPVCPU

  • up to and including serial number 20081affected

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Root cause

Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

1function expand(node) {2  return node.children.map(expand);3}

1const MAX_DEPTH = 32;2function expand(node, depth = 0) {3  if (depth > MAX_DEPTH) throw new Error("too deep");4  return node.children.map((c) => expand(c, depth + 1));5}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.