CVE-2021-34566 json
WAGO I/O-Check Service prone to Memory Overflow
published 2022-11-09 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21216
- cvss
- 9.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.4%
- EPSS 1.4% chance of exploitation in 30 days, percentile 71%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- wago 750-8100_firmware 18
- wago 750-8101_firmware 18
- wago 750-8101/025-000_firmware 18
- wago 750-8102_firmware 18
- wago 750-8102/025-000_firmware 18
- wago 750-8202_firmware 18
- wago 750-8202/000-011_firmware 18
- wago 750-8202/000-012_firmware 18
- wago 750-8202/000-022_firmware 18
- wago 750-8202/025-000_firmware 18
- wago 750-8202/025-001_firmware 18
- wago 750-8202/025-002_firmware 18
- wago 750-8202/040-000_firmware 18
- wago 750-8202/040-001_firmware 18
- wago 752-8303/8000-002_firmware 18
- wago 762-4101_firmware 18
- wago 762-4102_firmware 18
- wago 762-4103_firmware 18
- wago 762-4104_firmware 18
- wago 762-4201/8000-001_firmware 18
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 18 mo ago
Exploit prediction
1.35% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H |
Affected products
- WAGO 750-81xx/xxx-xxxFW
- WAGO 750-82xx/xxx-xxx
- WAGO 752-8303/8000-0002
- WAGO 762-4xxx
- WAGO 762-5xxx
- WAGO 762-6xxx
Classification
- Weakness
-
- CWE-120 Buffer Copy without Checking Size of Input
References
-
cert.vde.com
/en/advisories/VDE-2020-036/
vendor-advisory
Sources
- CVE List CVE-2021-34566
- NVD CVE-2021-34566
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