critical
9.1
CWE
120
Advisory Published
Updated

CVE-2021-34566: WAGO I/O-Check Service prone to Memory Overflow

First published: Wed Nov 09 2022(Updated: )

In WAGO I/O-Check Service in multiple products an unauthenticated remote attacker can send a specially crafted packet containing OS commands to crash the iocheck process and write memory resulting in loss of integrity and DoS.

Credit: info@cert.vde.com

Affected SoftwareAffected VersionHow to fix
WAGO 750-8100 firmware<18
WAGO 750-8100 firmware=18
WAGO 750-8100 firmware=18-patch_1
WAGO 750-8100 firmware=18-patch_2
WAGO 750-8100 firmware
WAGO 750-8101 firmware<18
WAGO 750-8101 firmware=18
WAGO 750-8101 firmware=18-patch_1
WAGO 750-8101 firmware=18-patch_2
WAGO 750-8101 firmware
WAGO 750-8101/025-000 firmware<18
WAGO 750-8101/025-000 firmware=18
WAGO 750-8101/025-000 firmware=18-patch_1
WAGO 750-8101/025-000 firmware=18-patch_2
WAGO 750-8101/025-000
WAGO Ethernet Firmware<18
WAGO Ethernet Firmware=18
WAGO Ethernet Firmware=18-patch_1
WAGO Ethernet Firmware=18-patch_2
WAGO 750-8102 firmware
WAGO 750-8102 firmware<18
WAGO 750-8102 firmware=18
WAGO 750-8102 firmware=18-patch_1
WAGO 750-8102 firmware=18-patch_2
WAGO 750-8102/025-000
WAGO 750-8202/025-002 Firmware<18
WAGO 750-8202/025-002 Firmware=18
WAGO 750-8202/025-002 Firmware=18-patch_1
WAGO 750-8202/025-002 Firmware=18-patch_2
WAGO 750-8202 Firmware
WAGO 750-8202/000-011 firmware<18
WAGO 750-8202/000-011 firmware=18
WAGO 750-8202/000-011 firmware=18-patch_1
WAGO 750-8202/000-011 firmware=18-patch_2
WAGO 750-8202/000-011
WAGO 750-8202/000-012 firmware<18
WAGO 750-8202/000-012 firmware=18
WAGO 750-8202/000-012 firmware=18-patch_1
WAGO 750-8202/000-012 firmware=18-patch_2
WAGO 750-8202
WAGO 750-8202/000-022 firmware<18
WAGO 750-8202/000-022 firmware=18
WAGO 750-8202/000-022 firmware=18-patch_1
WAGO 750-8202/000-022 firmware=18-patch_2
WAGO 750-8202
WAGO 750-8202/025-000 firmware<18
WAGO 750-8202/025-000 firmware=18
WAGO 750-8202/025-000 firmware=18-patch_1
WAGO 750-8202/025-000 firmware=18-patch_2
WAGO 750-8202/025-000
WAGO 750-8202/025-001 Firmware<18
WAGO 750-8202/025-001 Firmware=18
WAGO 750-8202/025-001 Firmware=18-patch_1
WAGO 750-8202/025-001 Firmware=18-patch_2
WAGO 750-8202/025-001
WAGO 750-8202/025-002 firmware<18
WAGO 750-8202/025-002 firmware=18
WAGO 750-8202/025-002 firmware=18-patch_1
WAGO 750-8202/025-002 firmware=18-patch_2
WAGO 750-8202/025-002
WAGO 750-8202/040-000 firmware<18
WAGO 750-8202/040-000 firmware=18
WAGO 750-8202/040-000 firmware=18-patch_1
WAGO 750-8202/040-000 firmware=18-patch_2
WAGO 750-8202/040-000
WAGO 750-8202/040-001 firmware<18
WAGO 750-8202/040-001 firmware=18
WAGO 750-8202/040-001 firmware=18-patch_1
WAGO 750-8202/040-001 firmware=18-patch_2
WAGO 750-8202/040-001
WAGO 752-8303/8000-002 firmware<18
WAGO 752-8303/8000-002 firmware=18
WAGO 752-8303/8000-002 firmware=18-patch_1
WAGO 752-8303/8000-002 firmware=18-patch_2
WAGO 752-8303/8000-002
WAGO 762-4101<18
WAGO 762-4101=18
WAGO 762-4101=18-patch_1
WAGO 762-4101=18-patch_2
WAGO 762-4101 firmware
WAGO 762-4102 firmware<18
WAGO 762-4102 firmware=18
WAGO 762-4102 firmware=18-patch_1
WAGO 762-4102 firmware=18-patch_2
WAGO 762-4102 firmware
WAGO 762-4103 firmware<18
WAGO 762-4103 firmware=18
WAGO 762-4103 firmware=18-patch_1
WAGO 762-4103 firmware=18-patch_2
WAGO 762-4103 firmware
WAGO 762-4104<18
WAGO 762-4104=18
WAGO 762-4104=18-patch_1
WAGO 762-4104=18-patch_2
WAGO 762-4104 firmware
WAGO 762-4201/8000-001 firmware<18
WAGO 762-4201/8000-001 firmware=18
WAGO 762-4201/8000-001 firmware=18-patch_1
WAGO 762-4201/8000-001 firmware=18-patch_2
WAGO 762-4201/8000-001
WAGO 762-4202/8000-001 firmware<18
WAGO 762-4202/8000-001 firmware=18
WAGO 762-4202/8000-001 firmware=18-patch_1
WAGO 762-4202/8000-001 firmware=18-patch_2
WAGO 762-4202/8000-001
WAGO 762-4203/8000-001 firmware<18
WAGO 762-4203/8000-001 firmware=18
WAGO 762-4203/8000-001 firmware=18-patch_1
WAGO 762-4203/8000-001 firmware=18-patch_2
WAGO 762-4203/8000-001
WAGO 762-4204/8000-001 firmware<18
WAGO 762-4204/8000-001 firmware=18
WAGO 762-4204/8000-001 firmware=18-patch_1
WAGO 762-4204/8000-001 firmware=18-patch_2
WAGO 762-4204/8000-001
WAGO 762-4205/8000-001 firmware<18
WAGO 762-4205/8000-001 firmware=18
WAGO 762-4205/8000-001 firmware=18-patch_1
WAGO 762-4205/8000-001 firmware=18-patch_2
WAGO 762-4205/8000-001
WAGO 762-4205/8000-002 firmware<18
WAGO 762-4205/8000-002 firmware=18
WAGO 762-4205/8000-002 firmware=18-patch_1
WAGO 762-4205/8000-002 firmware=18-patch_2
WAGO 762-4205/8000-002
WAGO 762-4206/8000-001 firmware<18
WAGO 762-4206/8000-001 firmware=18
WAGO 762-4206/8000-001 firmware=18-patch_1
WAGO 762-4206/8000-001 firmware=18-patch_2
WAGO 762-4206/8000-001
WAGO 762-4206/8000-002 firmware<18
WAGO 762-4206/8000-002 firmware=18
WAGO 762-4206/8000-002 firmware=18-patch_1
WAGO 762-4206/8000-002 firmware=18-patch_2
WAGO 762-4206/8000-002
WAGO 762-4301/8000-002 firmware<18
WAGO 762-4301/8000-002 firmware=18
WAGO 762-4301/8000-002 firmware=18-patch_1
WAGO 762-4301/8000-002 firmware=18-patch_2
WAGO 762-4301/8000-002
WAGO 762-4302/8000-002 firmware<18
WAGO 762-4302/8000-002 firmware=18
WAGO 762-4302/8000-002 firmware=18-patch_1
WAGO 762-4302/8000-002 firmware=18-patch_2
WAGO 762-4302/8000-002
WAGO 762-4303/8000-002 firmware<18
WAGO 762-4303/8000-002 firmware=18
WAGO 762-4303/8000-002 firmware=18-patch_1
WAGO 762-4303/8000-002 firmware=18-patch_2
WAGO 762-4303/8000-002
WAGO 762-4304/8000-002 firmware<18
WAGO 762-4304/8000-002 firmware=18
WAGO 762-4304/8000-002 firmware=18-patch_1
WAGO 762-4304/8000-002 firmware=18-patch_2
WAGO 762-4304/8000-002
WAGO 762-4305/8000-002 firmware<18
WAGO 762-4305/8000-002 firmware=18
WAGO 762-4305/8000-002 firmware=18-patch_1
WAGO 762-4305/8000-002 firmware=18-patch_2
WAGO 762-4305/8000-002
WAGO 762-4306/8000-002 firmware<18
WAGO 762-4306/8000-002 firmware=18
WAGO 762-4306/8000-002 firmware=18-patch_1
WAGO 762-4306/8000-002 firmware=18-patch_2
WAGO 762-4306/8000-002
WAGO 762-5203/8000-001 firmware<18
WAGO 762-5203/8000-001 firmware=18
WAGO 762-5203/8000-001 firmware=18-patch_1
WAGO 762-5203/8000-001 firmware=18-patch_2
WAGO 762-5203/8000-001
WAGO 762-5204/8000-001 firmware<18
WAGO 762-5204/8000-001 firmware=18
WAGO 762-5204/8000-001 firmware=18-patch_1
WAGO 762-5204/8000-001 firmware=18-patch_2
WAGO 762-5204/8000-001
WAGO 762-5205/8000-001 firmware<18
WAGO 762-5205/8000-001 firmware=18
WAGO 762-5205/8000-001 firmware=18-patch_1
WAGO 762-5205/8000-001 firmware=18-patch_2
WAGO 762-5205/8000-001
WAGO 762-5206/8000-001 firmware<18
WAGO 762-5206/8000-001 firmware=18
WAGO 762-5206/8000-001 firmware=18-patch_1
WAGO 762-5206/8000-001 firmware=18-patch_2
WAGO 762-5206/8000-001
WAGO 762-5303/8000-002 firmware<18
WAGO 762-5303/8000-002 firmware=18
WAGO 762-5303/8000-002 firmware=18-patch_1
WAGO 762-5303/8000-002 firmware=18-patch_2
WAGO 762-5303/8000-002
WAGO 762-5304/8000-002 firmware<18
WAGO 762-5304/8000-002 firmware=18
WAGO 762-5304/8000-002 firmware=18-patch_1
WAGO 762-5304/8000-002 firmware=18-patch_2
WAGO 762-5304/8000-002
WAGO 762-5305/8000-002 firmware<18
WAGO 762-5305/8000-002 firmware=18
WAGO 762-5305/8000-002 firmware=18-patch_1
WAGO 762-5305/8000-002 firmware=18-patch_2
WAGO 762-5305/8000-002
WAGO 762-5306/8000-002 firmware<18
WAGO 762-5306/8000-002 firmware=18
WAGO 762-5306/8000-002 firmware=18-patch_1
WAGO 762-5306/8000-002 firmware=18-patch_2
WAGO 762-5306/8000-002
WAGO 762-6201/8000-001 firmware<18
WAGO 762-6201/8000-001 firmware=18
WAGO 762-6201/8000-001 firmware=18-patch_1
WAGO 762-6201/8000-001 firmware=18-patch_2
WAGO 762-6201/8000-001
WAGO 762-6202/8000-001 firmware<18
WAGO 762-6202/8000-001 firmware=18
WAGO 762-6202/8000-001 firmware=18-patch_1
WAGO 762-6202/8000-001 firmware=18-patch_2
WAGO 762-6202/8000-001
WAGO 762-6203/8000-001 firmware<18
WAGO 762-6203/8000-001 firmware=18
WAGO 762-6203/8000-001 firmware=18-patch_1
WAGO 762-6203/8000-001 firmware=18-patch_2
WAGO 762-6203/8000-001
WAGO 762-6204/8000-001 firmware<18
WAGO 762-6204/8000-001 firmware=18
WAGO 762-6204/8000-001 firmware=18-patch_1
WAGO 762-6204/8000-001 firmware=18-patch_2
WAGO 762-6204/8000-001
WAGO 762-6301/8000-002 firmware<18
WAGO 762-6301/8000-002 firmware=18
WAGO 762-6301/8000-002 firmware=18-patch_1
WAGO 762-6301/8000-002 firmware=18-patch_2
WAGO 762-6301/8000-002
WAGO 762-6302/8000-002 firmware<18
WAGO 762-6302/8000-002 firmware=18
WAGO 762-6302/8000-002 firmware=18-patch_1
WAGO 762-6302/8000-002 firmware=18-patch_2
WAGO 762-6302/8000-002
WAGO 762-6303/8000-002 firmware<18
WAGO 762-6303/8000-002 firmware=18
WAGO 762-6303/8000-002 firmware=18-patch_1
WAGO 762-6303/8000-002 firmware=18-patch_2
WAGO 762-6303/8000-002
WAGO 762-6304/8000-002 firmware<18
WAGO 762-6304/8000-002 firmware=18
WAGO 762-6304/8000-002 firmware=18-patch_1
WAGO 762-6304/8000-002 firmware=18-patch_2
WAGO 762-6304/8000-002

Never miss a vulnerability like this again

Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.

Read MoreStart Free Trial

Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-34566?

    CVE-2021-34566 is considered critical due to its potential to allow unauthenticated remote attackers to crash the affected WAGO I/O-Check Service.

  • How do I fix CVE-2021-34566?

    To mitigate CVE-2021-34566, it is recommended to apply the latest firmware updates provided by WAGO.

  • Can CVE-2021-34566 be exploited remotely?

    Yes, CVE-2021-34566 can be exploited remotely without authentication by sending specially crafted packets.

  • What affected products are involved in CVE-2021-34566?

    CVE-2021-34566 affects various WAGO I/O-Check Service products, including firmware versions up to 18.

  • What damage can CVE-2021-34566 cause?

    Exploitation of CVE-2021-34566 can lead to denial of service and loss of integrity in the affected systems.

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2025 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203