CVE-2021-34581

highpriority · track · 30EPSS 0.010 · 63 %ileDEEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
1.02% (63rd) EPSS
CVSS 7.8 · high
Is it mine?
14 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · nvd · wago_psirt

EPSS · scored 2026-10-28

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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • Fixedwago_psirt

    Update the device to the latest FW version.

  • Mitigationwago_psirt

    - Restrict network access to the device. - Do not directly connect the device to the internet - Disable unused TCP/UDP-ports - Disable Web Based Management ports 80/443 after configuration phase.

02

cvss

Technical severity, 0–10. One row per scoring source.

7.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.8

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · info@cert.vde.comexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · WAGO PSIRT DE
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-772USprimaryCWE-772US
04

affected products (14)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • VDE-2021-038WAGO: OpenSSL DoS Vulnerability in PLCs2021-08-31csaf · wago_psirtDE

    WAGO controllers have always been designed for easy connection to IT infrastructure. Even controllers from legacy product lines support encryption standards to ensure secure communication. With special crafted requests it is possible to bring the device out of operation. All listed devices are vulnerable for this denial of service attack.

06

also known as (3)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdnvdwago_psirtNVDCVE.orgMITRE
published 2021-08-31modified 2026-06-17
09

references (4)

External citations — patches, advisories, analysis.

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