CVE-2018-7843
mediumpriority · track · 41EPSS 0.032 · 88 %ileexploit · PoCEURUUSEPSS · scored 2026-10-26
A CWE-248: Uncaught Exception vulnerability exists in all versions of the Modicon M580, Modicon M340, Modicon Quantum, and Modicon Premium which could cause denial of service when reading memory blocks with an invalid data size or with an invalid data offset in the controller over Modbus.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedModicon M340 Firmware Versions prior to v3.10 installed on Modicon M340 Controllercisa_csaf_ot
Version sv3.60 of Modicon M340 includes a fix for this vulnerability and is available for download here: STEP 1: Update software and firmware • On the engineering workstation, update to EcoStruxure Control Expert v16.0 or later: https://www.se.com/ww/en/product-range/548-ecostruxure-control-expert-unity-pro/#software-and-firmware • On the Modicon M340 controller, update to firmware v3.60 or above: https://www.se.com/ww/en/product-range/1468- modicon-m340/#software-and-firmware STEP 2: Update projects in EcoStruxure Control Expert by: • Setting up an application password in the project properties • Changing the version of the controller firmware to match the new firmware version of the target controller STEP 3: Rebuild and transfer projects in EcoStruxure Control Expert: • Rebuild all current projects • Transfer them to Modicon controllers
https://www.se.com/ww/en/product-range/1468-modicon-m340/#software-and-firmware - FixedModicon M580 Firmware Versions prior to v2.80 installed on Modicon M580 Controllercisa_csaf_ot
Version sv4.20 of Modicon M580 includes a fix for this vulnerability and is available for download here: STEP 1: Update software and firmware. • On the engineering workstation, update to EcoStruxure Control Expert v16.0: https://www.se.com/ww/en/product-range/548-ecostruxure-control-expert-unity-pro/#software-and-firmware • On the Modicon M580 controller, update to firmware SV4.20 or above: https://www.se.com/ww/en/product-range/62098-modicon-m580-epac/#software-and-firmware STEP 2: Update projects in EcoStruxure Control Expert by: • Setting up an application password in the project properties • Changing the version of the controller firmware to match the new firmware version of the target controller STEP 3: Rebuild and transfer projects in EcoStruxure Control Expert: • Rebuild all current projects
https://www.se.com/ww/en/product-range/62098-modicon-m580-epac/#software-and-firmware - FixedModicon Premium Firmware Versions prior to v3.20 installed on Modicon Premium Controllercisa_csaf_ot
Please contact your Schneider Electric customer support to get Premium V3.20 firmware. TSXP57104M [C] TSXP57154M [C] TSXP571634M [C] TSXP57204M [C] TSXP572634M [C] TSXP57254M [C] TSXP57304M [C] TSXP573634M [C] TSXP57354M [C] TSXP574634M [C] TSXP57454M [C] TSXP575634M [C] TSXP57554M [C] TSXP576634M [C] TSXH5724M [C] TSXH5744M [C]
https://www.se.com/us/en/work/support/ - FixedModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU65150 [C] & 140CPU65160 [C]cisa_csaf_ot
Version v3.60 of Modicon Quantum includes a fix for this vulnerability and is available for download here: 140CPU65150 [C] & 140CPU65160 [C] - https://www.schneider-electric.com/en/download/document/Quantum_140CPU651X0_SV3.60
https://www.schneider-electric.com/en/download/document/Quantum_140CPU651X0_SV3.60 - FixedModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU65260 [C]cisa_csaf_ot
Version v3.60 of Modicon Quantum includes a fix for this vulnerability and is available for download here: 140CPU65260 [C] - https://www.schneider-electric.com/en/download/document/Quantum_140CPU65260_SV3.60
https://www.schneider-electric.com/en/download/document/Quantum_140CPU65260_SV3.60 - FixedModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU65860 [C]cisa_csaf_ot
Version v3.60 of Modicon Quantum includes a fix for this vulnerability and is available for download here: 140CPU65860 [C] - https://www.schneider-electric.com/en/download/document/Quantum_140CPU65860_SV3.60
https://www.schneider-electric.com/en/download/document/Quantum_140CPU65860_SV3.60 - FixedModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67060 [C]cisa_csaf_ot
Version v3.60 of Modicon Quantum includes a fix for this vulnerability and is available for download here: 140CPU67060 [C] - https://www.schneider-electric.com/en/download/document/Quantum_140CPU67060_SV3.60
https://www.schneider-electric.com/en/download/document/Quantum_140CPU67060_SV3.60 - FixedModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67160 [C]cisa_csaf_ot
Version v3.60 of Modicon Quantum includes a fix for this vulnerability and is available for download here: 140CPU67160 [C] - https://www.schneider-electric.com/en/download/document/Quantum_140CPU67160_SV3.60
https://www.schneider-electric.com/en/download/document/Quantum_140CPU67160_SV3.60 - FixedModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67260 [C]cisa_csaf_ot
Version v3.60 of Modicon Quantum includes a fix for this vulnerability and is available for download here: 140CPU67260 [C] - https://www.schneider-electric.com/en/download/document/Quantum_140CPU67260_SV3.60
https://www.schneider-electric.com/en/download/document/Quantum_140CPU67260_SV3.60 - FixedModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67261 [C]cisa_csaf_ot
Version v3.60 of Modicon Quantum includes a fix for this vulnerability and is available for download here: 140CPU67261 [C] - https://www.schneider-electric.com/en/download/document/Quantum_140CPU67261_SV3.60
https://www.schneider-electric.com/en/download/document/Quantum_140CPU67261_SV3.60 - FixedModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67861 [C]cisa_csaf_ot
Version v3.60 of Modicon Quantum includes a fix for this vulnerability and is available for download here: 140CPU67861 [C] - https://www.schneider-electric.com/en/download/document/Quantum_140CPU67861_SV3.60
https://www.schneider-electric.com/en/download/document/Quantum_140CPU67861_SV3.60 - MitigationModicon M340 Firmware Versions prior to v3.10 installed on Modicon M340 Controllercisa_csaf_ot
It is recommended to apply the following mitigations to reduce the risk of exploitation: • Set up an application password in the project properties • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List following the recommendations of the user manuals: o “Modicon M340 for Ethernet Communications Modules and Processors User Manual” in chapter “Messaging Configuration Parameters”: https://www.se.com/ww/en/download/document/31007131K01000/ • Set up a secure communication according to the following guideline “Modicon Controllers Platform Cyber Security Reference Manual,” in chapter “Setup secured communications”: https://www.se.com/ww/en/download/document/EIO0000001999/ • Consider use of external firewall devices such as EAGLE40-07 from Belden to establish VPN connections for M340 & M580 architectures. For more details refer to the chapter “How to protect M580 and M340 architectures with EAGLE40 using VPN”: https://www.se.com/ww/en/download/document/EIO0000001999/
https://www.se.com/ww/en/download/document/31007131K01000/ - MitigationModicon M580 Firmware Versions prior to v2.80 installed on Modicon M580 Controllercisa_csaf_ot
It is recommended to apply the following mitigations to reduce the risk of exploitation: • Set up an application password in the project properties • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List following the recommendations of the user manuals: https://www.se.com/ww/en/download/document/EIO0000001578/ • Set up a secure communication according to the following guideline “Modicon Controllers Platform Cyber Security Reference Manual,” in chapter “Setup secured communications”: https://www.se.com/ww/en/download/document/EIO0000001999/ NOTE: Use a BMENOC module and follow the instructions to configure IPSEC feature as described in the guideline “Modicon M580 - BMENOC03.1 Ethernet Communications Schneider Electric Security Notification Module, Installation and Configuration Guide” in the chapter “Configuring IPSEC communications”: https://www.se.com/ww/en/download/document/HRB62665/ OR • Use a BMENUA0100 module and follow the instructions to configure IPSEC feature as described in the chapter “Configuring the BMENUA0100 Cybersecurity Settings”: https://www.se.com/ww/en/download/document/PHA83350 OR • Consider using external firewall devices such as EAGLE40-07 from Belden to establish VPN connections for M340 and M580 architectures. For more details refer to the chapter “How to protect M580 and M340 architectures with EAGLE40 using VPN”: https://www.se.com/ww/en/download/document/EIO0000001999/ • Ensure the M580 CPU is running with the memory protection activated by configuring the input bit to a physical input, for more details refer to the following guideline “Modicon Controllers Platform Cyber Security Reference Manual”, “CPU Memory Protection section”: https://www.schneider-electric.com/en/download/document/EIO0000001999/ NOTE: The CPU memory protection cannot be configured with M580 Hot Standby CPUs. In such cases, use IPsec encrypted communication.
https://www.se.com/ww/en/download/document/EIO0000001999/ - MitigationModicon Premium Firmware Versions prior to v3.20 installed on Modicon Premium Controllercisa_csaf_ot
Schneider Electric’s Modicon Premium controllers have reached their end of life and are no longer commercially available. They have been replaced by the Modicon M580 ePAC controller, our most current product offer. Customers should strongly consider migrating to the Modicon M580 ePAC. Please contact your local Schneider Electric technical support for more information. To mitigate the risks associated with Modbus/ weaknesses, users should immediately: • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List following the recommendations of the user manual “Premium and Atrium using EcoStruxure Control Expert - Ethernet Network Modules, User Manual” in chapters “Connection configuration parameters / TCP/IP Services Configuration Parameters / Connection Configuration Parameters”: https://www.se.com/ww/en/download/document/35006192K01000/
https://www.se.com/ww/en/download/document/35006192K01000/ - MitigationModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU65150 [C] & 140CPU65160 [C]cisa_csaf_ot
Schneider Electric’s Modicon Quantum and Quantum Safety controllers have reached their end of life and are no longer commercially available. They have been replaced by the Modicon M580 or M580 Safety ePAC controller, our most current product offer. Customers should strongly consider migrating to the Modicon M580 ePAC. Please contact your local Schneider Electric technical support for more information. To mitigate the risks associated with Modbus/ weaknesses, users should immediately: • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List feature as mentioned in “Quantum using EcoStruxure Control Expert - TCP/IP Configuration, User Manual” in chapter “Software Settings for Ethernet Communication / Messaging / Quantum NOE Ethernet Messaging Configuration”: https://www.se.com/ww/en/download/document/33002467K01000/
https://www.se.com/ww/en/download/document/33002467K01000/ - MitigationModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU65260 [C]cisa_csaf_ot
Schneider Electric’s Modicon Quantum and Quantum Safety controllers have reached their end of life and are no longer commercially available. They have been replaced by the Modicon M580 or M580 Safety ePAC controller, our most current product offer. Customers should strongly consider migrating to the Modicon M580 ePAC. Please contact your local Schneider Electric technical support for more information. To mitigate the risks associated with Modbus/ weaknesses, users should immediately: • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List feature as mentioned in “Quantum using EcoStruxure Control Expert - TCP/IP Configuration, User Manual” in chapter “Software Settings for Ethernet Communication / Messaging / Quantum NOE Ethernet Messaging Configuration”: https://www.se.com/ww/en/download/document/33002467K01000/
https://www.se.com/ww/en/download/document/33002467K01000/ - MitigationModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU65860 [C]cisa_csaf_ot
Schneider Electric’s Modicon Quantum and Quantum Safety controllers have reached their end of life and are no longer commercially available. They have been replaced by the Modicon M580 or M580 Safety ePAC controller, our most current product offer. Customers should strongly consider migrating to the Modicon M580 ePAC. Please contact your local Schneider Electric technical support for more information. To mitigate the risks associated with Modbus/ weaknesses, users should immediately: • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List feature as mentioned in “Quantum using EcoStruxure Control Expert - TCP/IP Configuration, User Manual” in chapter “Software Settings for Ethernet Communication / Messaging / Quantum NOE Ethernet Messaging Configuration”: https://www.se.com/ww/en/download/document/33002467K01000/
https://www.se.com/ww/en/download/document/33002467K01000/ - MitigationModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67060 [C]cisa_csaf_ot
Schneider Electric’s Modicon Quantum and Quantum Safety controllers have reached their end of life and are no longer commercially available. They have been replaced by the Modicon M580 or M580 Safety ePAC controller, our most current product offer. Customers should strongly consider migrating to the Modicon M580 ePAC. Please contact your local Schneider Electric technical support for more information. To mitigate the risks associated with Modbus/ weaknesses, users should immediately: • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List feature as mentioned in “Quantum using EcoStruxure Control Expert - TCP/IP Configuration, User Manual” in chapter “Software Settings for Ethernet Communication / Messaging / Quantum NOE Ethernet Messaging Configuration”: https://www.se.com/ww/en/download/document/33002467K01000/
https://www.se.com/ww/en/download/document/33002467K01000/ - MitigationModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67160 [C]cisa_csaf_ot
Schneider Electric’s Modicon Quantum and Quantum Safety controllers have reached their end of life and are no longer commercially available. They have been replaced by the Modicon M580 or M580 Safety ePAC controller, our most current product offer. Customers should strongly consider migrating to the Modicon M580 ePAC. Please contact your local Schneider Electric technical support for more information. To mitigate the risks associated with Modbus/ weaknesses, users should immediately: • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List feature as mentioned in “Quantum using EcoStruxure Control Expert - TCP/IP Configuration, User Manual” in chapter “Software Settings for Ethernet Communication / Messaging / Quantum NOE Ethernet Messaging Configuration”: https://www.se.com/ww/en/download/document/33002467K01000/
https://www.se.com/ww/en/download/document/33002467K01000/ - MitigationModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67260 [C]cisa_csaf_ot
Schneider Electric’s Modicon Quantum and Quantum Safety controllers have reached their end of life and are no longer commercially available. They have been replaced by the Modicon M580 or M580 Safety ePAC controller, our most current product offer. Customers should strongly consider migrating to the Modicon M580 ePAC. Please contact your local Schneider Electric technical support for more information. To mitigate the risks associated with Modbus/ weaknesses, users should immediately: • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List feature as mentioned in “Quantum using EcoStruxure Control Expert - TCP/IP Configuration, User Manual” in chapter “Software Settings for Ethernet Communication / Messaging / Quantum NOE Ethernet Messaging Configuration”: https://www.se.com/ww/en/download/document/33002467K01000/
https://www.se.com/ww/en/download/document/33002467K01000/ - MitigationModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67261 [C]cisa_csaf_ot
Schneider Electric’s Modicon Quantum and Quantum Safety controllers have reached their end of life and are no longer commercially available. They have been replaced by the Modicon M580 or M580 Safety ePAC controller, our most current product offer. Customers should strongly consider migrating to the Modicon M580 ePAC. Please contact your local Schneider Electric technical support for more information. To mitigate the risks associated with Modbus/ weaknesses, users should immediately: • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List feature as mentioned in “Quantum using EcoStruxure Control Expert - TCP/IP Configuration, User Manual” in chapter “Software Settings for Ethernet Communication / Messaging / Quantum NOE Ethernet Messaging Configuration”: https://www.se.com/ww/en/download/document/33002467K01000/
https://www.se.com/ww/en/download/document/33002467K01000/ - MitigationModicon Quantum Firmware Versions prior to v3.60 installed on Modicon Quantum Controller 140CPU67861 [C]cisa_csaf_ot
Schneider Electric’s Modicon Quantum and Quantum Safety controllers have reached their end of life and are no longer commercially available. They have been replaced by the Modicon M580 or M580 Safety ePAC controller, our most current product offer. Customers should strongly consider migrating to the Modicon M580 ePAC. Please contact your local Schneider Electric technical support for more information. To mitigate the risks associated with Modbus/ weaknesses, users should immediately: • Set up network segmentation and implement a firewall to block all unauthorized access to port 502/TCP • Configure the Access Control List feature as mentioned in “Quantum using EcoStruxure Control Expert - TCP/IP Configuration, User Manual” in chapter “Software Settings for Ethernet Communication / Messaging / Quantum NOE Ethernet Messaging Configuration”: https://www.se.com/ww/en/download/document/33002467K01000/
https://www.se.com/ww/en/download/document/33002467K01000/
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
exploits (1)
Public proof-of-concept and weaponised exploit code.
- yanissec/CVE-2018-7843CVE-2018-7843PoC · poc_in_github
affected products (31)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- ICSA-25-114-01Schneider Electric Modicon Controllers (Update A)2019-05-14icsa · cisa_csaf_otUS
Schneider Electric is aware of multiple vulnerabilities in its Modicon Controller products. The [Modicon Programmable Automation controllers](https://www.se.com/ww/en/product-subcategory/3950-pac-programmable-automation-controllers/) are used for complex networked communication, display and control applications Failure to apply the mitigations or remediations provided below may risk execution of unsolicited command on the PLC which could result in a loss of availability of the controller.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://nvd.nist.gov/vuln/detail/CVE-2018-7843cnnvd
- https://talosintelligence.com/vulnerability_reports/TALOS-2018-0738cnnvd
- https://www.schneider-electric.com/en/download/document/SEVD-2019-134-11/cnnvd
- https://www.talosintelligence.com/vulnerability_reports/TALOS-2018-0738cnnvd
- https://www.schneider-electric.com/en/download/document/SEVD-2019-134-11/enisa_euvd
- https://www.talosintelligence.com/vulnerability_reports/TALOS-2018-0738enisa_euvd
- https://www.schneider-electric.com/en/download/document/SEVD-2019-134-11/Vendor Advisorynvd
- https://www.talosintelligence.com/vulnerability_reports/TALOS-2018-0738ExploitThird Party Advisorynvd
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