CVE-2021-34580

mediumpriority · track · 30EPSS 0.010 · 64 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.04% (64th) EPSS

CVSS 5 · medium

Is it mine?

12 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · helmholz_psirt · mb_connect_line_psirt

EPSS · scored 2026-10-22

In mymbCONNECT24, mbCONNECT24 <= 2.9.0 an unauthenticated user can enumerate valid backend users by checking what kind of response the server sends for crafted invalid login attempts.

remediations

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

A vendor fix is available.

Fixedmb_connect_line_psirt
Update mbCONNECT24/mymbCONNECT24 to 2.10.1
Fixedhelmholz_psirt
Update myREX24/myREX24-virtual to 2.10.1

cvss

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

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:P/I:N/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · info@cert.vde.comexploitability 3.9 · impact 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · Helmholz PSIRT

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · MB connect line PSIRT

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-203USprimaryCWE-204USCWE-204USCWE-204US

affected products (12)

Products and version ranges known to be affected.

MB connect line mbCONNECT24≤ 2.9.0 ≤2.9.0enisa_euvdEU
MB connect line mymbCONNECT24≤ 2.9.0 ≤2.9.0enisa_euvdEU
Firmware 2.10.1 installed on myREX24all versionsfixedhelmholz_psirtDE
Firmware 2.10.1 installed on myREX24-virtualall versionsfixedhelmholz_psirtDE
Firmware <=2.9.0 installed on myREX24all versionshelmholz_psirtDE
Firmware <=2.9.0 installed on myREX24-virtualall versionshelmholz_psirtDE
MB connect line mbCONNECT24≤ 2.9.0mb_connect_line_psirtDE
MB connect line mbCONNECT24all versionsfixedmb_connect_line_psirtDE
MB connect line mymbCONNECT24≤ 2.9.0mb_connect_line_psirtDE
MB connect line mymbCONNECT24all versionsfixedmb_connect_line_psirtDE
mbconnectline mbconnect24≤ 2.9.0nvdUScpe:2.3:a:mbconnectline:mbconnect24:*:*:*:*:*:*:*:*
mbconnectline mymbconnect24≤ 2.9.0nvdUScpe:2.3:a:mbconnectline:mymbconnect24:*:*:*:*:*:*:*:*

advisories (2)

Vendor and ecosystem advisories describing this.

VDE-2021-037MB connect line: Remote user enumeration in mbCONNECT24/mymbCONNECT242021-10-27csaf · mb_connect_line_psirtDE
An issue was discovered in the mymbCONNECT24 and mbCONNECT24 software in all versions through V2.9.0.
VDE-2021-058Helmholz: Remote user enumeration in myREX24/myREX24-virtual2021-12-08csaf · helmholz_psirtDE
An issue was discovered in the myREX24 and myREX24-virtual software in all versions through V2.9.0.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd helmholz_psirt mb_connect_line_psirt nvd NVD CVE.org MITRE

published 2021-10-27modified 2026-06-17

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+880 more

references (4)

External citations — patches, advisories, analysis.

scry

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