CyberSecBulletin
CVE-2022-34760NVD status: Modified

OPC UA Modicon Communication Module: Loop with Unreachable Exit Condition

CVE-2022-34760 is a high-severity loop with unreachable exit condition 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 0.8% chance of exploitation within 30 days, higher than 57% 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. Read the advisory on download.schneider-electric.com for workarounds and exact fixed builds.
  3. 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 ModuleBMENOR2200H V1.0Not stated
Schneider ElectricOpc Ua Module For M580 Firmware1.10 and earlierNot stated
Schneider ElectricX80 Advanced Rtu Module Firmware1.0Not 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-835: Loop with Unreachable Exit Condition ('Infinite Loop') vulnerability exists that could cause a denial of service of the webserver due to improper handling of the cookies. Affected Products: X80 advanced RTU Communication Module (BMENOR2200H) (V1.0), 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: Loop with Unreachable Exit Condition

The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop.

More Loop with Unreachable Exit Condition vulnerabilities (CWE-835)

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 Loop with Unreachable Exit Condition vulnerabilities

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