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Fencer Intel
high 7.1

CVE-2021-21559 json

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 th…

published 5y ago modified 4mo ago also EUVD-2021-8831

cvss
7.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

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.

Patch / fix

  • Dell NetWorker 19.4.0.2

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Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 7.1 CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD 3.1 5.3 CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
NVD 2.0 2.9 AV:A/AC:M/Au:N/C:N/I:P/A:N

Affected products

  • Dell NetWorker

Classification

Weakness
  • CWE-295 Improper Certificate Validation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.