Cyber Resilience

CVE-2021-30191

High

Published: 25 May 2021

Published
25 May 2021
Modified
15 August 2025
KEV Added
—
Patch
—
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0041 61.6th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-30191 is a high-severity Classic Buffer Overflow (CWE-120) vulnerability in Wago 750-893 Firmware. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 38.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

CODESYS V2 Web-Server before 1.1.9.20 has a a Buffer Copy without Checking the Size of the Input.

CWE(s)
CWE-120

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

wago
750-893 firmware
≤ fw08
wago
750-891 firmware
≤ fw08
wago
750-890 firmware
≤ fw08
wago
750-889 firmware
≤ fw15
wago
750-885 firmware
≤ fw15
wago
750-882 firmware
≤ fw15
wago
750-881 firmware
≤ fw15
wago
750-880 firmware
≤ fw16
wago
750-862 firmware
≤ fw08
wago
750-852 firmware
≤ fw15
+18 more product configuration(s) — see NVD for full list

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SC-27 Platform-independent Applications
addresses: CWE-120

Platform-independent managed code eliminates the need for unchecked native buffer copies that are the root cause of classic buffer overflows.

References