CyberSecBulletin
CVE-2024-0802NVD status: Deferred

MELSEC-Q Series Q03UDECPU: Incorrect Pointer Scaling

Published Updated By the CyberSecBulletin desk

CVE-2024-0802 is a critical-severity incorrect pointer scaling vulnerability in MELSEC-Q Series Q03UDECPU from Mitsubishi Electric, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected MELSEC-Q Series Q03UDECPU versions: The first 5 digits of serial No. "26061" and prior. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.07% chance of exploitation within 30 days, higher than 65% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update melsec_q-q03udecpu to xxxxx26061 or a later version.
  2. Update melsec_q-q04udehcpu to xxxxx26061 or a later version.
  3. Update melsec_q-q06udehcpu to xxxxx26061 or a later version.
  4. Read the advisory on mitsubishielectric.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Mitsubishi ElectricMELSEC-Q Series Q03UDECPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q04UDEHCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q06UDEHCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q10UDEHCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q13UDEHCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q20UDEHCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q26UDEHCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q50UDEHCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q100UDEHCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q03UDVCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q04UDVCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q06UDVCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q13UDVCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q26UDVCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q04UDPVCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q06UDPVCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q13UDPVCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-Q Series Q26UDPVCPUThe first 5 digits of serial No. "26061" and priorNot stated
Mitsubishi ElectricMELSEC-L Series L02CPUThe first 5 digits of serial No. "26041" and priorNot stated
Mitsubishi ElectricMELSEC-L Series L06CPUThe first 5 digits of serial No. "26041" and priorNot stated
Mitsubishi ElectricMELSEC-L Series L26CPUThe first 5 digits of serial No. "26041" and priorNot stated
Mitsubishi ElectricMELSEC-L Series L02CPU-PThe first 5 digits of serial No. "26041" and priorNot stated
Mitsubishi ElectricMELSEC-L Series L06CPU-PThe first 5 digits of serial No. "26041" and priorNot stated
Mitsubishi ElectricMELSEC-L Series L26CPU-PThe first 5 digits of serial No. "26041" and priorNot stated
Mitsubishi ElectricMELSEC-L Series L26CPU-BTThe first 5 digits of serial No. "26041" and priorNot stated

Version data comes from the organisation that assigned the CVE; 26 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (yd.MitsubishiElectric.co.jp).

Official description

Incorrect Pointer Scaling vulnerability in Mitsubishi Electric Corporation MELSEC-Q Series and MELSEC-L Series CPU modules allows a remote unauthenticated attacker to read arbitrary information from a target product or execute malicious code on a target product by sending a specially crafted packet.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incorrect Pointer Scaling

In C and C++, one may often accidentally refer to the wrong memory due to the semantics of when math operations are implicitly scaled.

How developers prevent this class of flaw

  • Use a platform with high-level memory abstractions.
  • Always use array indexing instead of direct pointer manipulation.
  • Use technologies for preventing buffer overflows.

More Incorrect Pointer Scaling vulnerabilities (CWE-468)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in MELSEC-Q Series Q03UDECPU

All MELSEC-Q Series Q03UDECPU vulnerabilities

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