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Status published
Critical
CVE-2021-34566
WAGO I/O-Check Service prone to Memory Overflow
Vulnerability Description
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.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- These vulnerabilities were reported to WAGO by Uri Katz of Claroty.
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Affected Vendor
WAGO
View all reports →Affected Software
750-81xx/xxx-xxxFW, 750-82xx/xxx-xxx, 752-8303/8000-0002, 762-4xxx, 762-5xxx, 762-6xxx
Vulnerable Versions:
FW1
Timeline
Official Publish:
November 9th, 2022
Last Modified:
May 1st, 2025
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H