CVE-2021-21559

lowpriority · track · 21EPSS 0.002 · 6 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.17% (6th) EPSS

CVSS 2.9 · low

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

Dell EMC NetWorker, versions 18.x, 19.1.x, 19.2.x 19.3.x, 19.4, and 19.4.0.1 contain an Improper Certificate Validation vulnerability in the client (NetWorker Management Console) components which uses SSL encrypted connection in order to communicate with the application server. An unauthenticated attacker in the same network collision domain as the NetWorker Management Console client could potentially exploit this vulnerability to perform man-in-the-middle attacks to intercept and tamper the traffic between the client and the application server.

cvss

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

7.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 2.9–7.1

v2.02.9lowAV:A/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 5.5 · impact 2.9

v3.15.3mediumCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 1.6 · impact 3.6

v3.17.1highCVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.17.1highCVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · security_alert@emc.comexploitability 1.2 · impact 5.9

v3.14.9mediumCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-295USprimary

affected products (2)

Products and version ranges known to be affected.

Dell Networkerunspecified → 19.4.0.2enisa_euvdEU
dell emc networker18.1.0.1 → 19.4.0.2nvdUScpe:2.3:a:dell:emc_networker:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-06-08modified 2026-06-17

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+1889 more

references (5)

External citations — patches, advisories, analysis.

scry

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