CVE-2021-21559

CVE-2021-21559 is a high-severity vulnerability in Dell Emc Networker with a CVSS 3.x base score of 7.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-295.

Key facts

Description

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.

Frequently asked questions

What is CVE-2021-21559?
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.
How severe is CVE-2021-21559?
CVE-2021-21559 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over an adjacent network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-21559 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21559?
CVE-2021-21559 affects Dell Emc Networker. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-21559?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-21559 published?
CVE-2021-21559 was published on 2021-06-08 and last updated on 2026-06-17.

References

Affected products (1)

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