No exploitation reported

CVE-2021-34581

No exploitation reported by the sources we read.

Published2021-08-31
WeaknessCWE-772

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

Missing Release of Resource after Effective Lifetime vulnerability in OpenSSL implementation of WAGO 750-831/xxx-xxx, 750-880/xxx-xxx, 750-881, 750-889 in versions FW4 up to FW15 allows an unauthenticated attacker to cause DoS on the device.

Timeline

dates in UTC

2021-08-3111:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-34581?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-34581?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Wago 750-831 firmwareversion to verify

Branch	Affected	Fixed in	Source
—	≥ fw4, ≤ fw15	no fix published	NVD

Wago 750-831\/000-002 firmwareversion to verify

Branch	Affected	Fixed in	Source
—	≥ fw4, ≤ fw15	no fix published	NVD

Wago 750-880 firmwareversion to verify

Branch	Affected	Fixed in	Source
—	≥ fw4, ≤ fw15	no fix published	NVD

6 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

No fix published by the sources we read yet. NVD record

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

CNACVSS 3.17.5read 2026-10-23
NVDCVSS 3.17.5read 2026-10-23
NVDCVSS 2.07.8read 2026-10-23
CNAweakness (CWE)CWE-772read 2026-10-23
NVDweakness (CWE)CWE-772read 2026-10-23
FIRST EPSSEPSS score1.0 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: 2021-08-31
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-34581?

Is CVE-2021-34581 actively exploited?

Active exploitation of CVE-2021-34581 has not been confirmed. Its EPSS score was 1.0% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-34581?

CVE-2021-34581 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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