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CVE-2022-34761NVD status: Modified

OPC UA Modicon Communication Module: NULL Pointer Dereference

CVE-2022-34761 is a high-severity NULL pointer dereference vulnerability in OPC UA Modicon Communication Module from Schneider Electric, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version V1.10 as the first without the flaw, so updating OPC UA Modicon Communication Module to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.92% chance of exploitation within 30 days, higher than 61% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update OPC UA Modicon Communication Module to V1.10 or a later version.
  2. Update X80 advanced RTU Communication Module to BMENOR2200H* or a later version.
  3. Read the advisory on download.schneider-electric.com for workarounds and exact fixed builds.
  4. 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
Schneider ElectricOPC UA Modicon Communication ModuleBMENUA0100 up to, but not including, V1.10V1.10
Schneider ElectricX80 advanced RTU Communication ModuleV2.01 up to, but not including, BMENOR2200H*BMENOR2200H*
Schneider ElectricOpc Ua Module For M580 Firmware1.10 and earlierNot stated
Schneider ElectricX80 Advanced Rtu Module Firmware2.01 and laterNot stated

Version data comes from the organisation that assigned the CVE. 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
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighCNA (se.com)
CVSS 3.17.5HighNVD

Official description

A CWE-476: NULL Pointer Dereference vulnerability exists that could cause a denial of service of the webserver when parsing JSON content type. Affected Products: X80 advanced RTU Communication Module (BMENOR2200H) (V2.01 and later), OPC UA Modicon Communication Module (BMENUA0100) (V1.10 and prior)

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

The underlying weakness: NULL Pointer Dereference

The product dereferences a pointer that it expects to be valid but is NULL.

How developers prevent this class of flaw

  • For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
  • Select a programming language that is not susceptible to these issues.
  • Check the results of all functions that return a value and verify that the value is non-null before acting upon it.

More NULL Pointer Dereference vulnerabilities (CWE-476)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in OPC UA Modicon Communication Module

All OPC UA Modicon Communication Module vulnerabilities

Recent NULL Pointer Dereference vulnerabilities

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