Is CVE-2021-21878 actively exploited?

No active exploitation of CVE-2021-21878 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-21878 be exploited remotely?

Yes. CVE-2021-21878 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-21878?

CVE-2021-21878 has a CVSS score of 4.9 (MEDIUM).

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MEDIUM

CVE-2021-21878

CWE-668Published: December 22, 2021· Updated: Jun 17, 2026

4.9

CVSS v3.1

Official Description

A local file inclusion vulnerability exists in the Web Manager Applications and FsBrowse functionality of Lantronix PremierWave 2050 8.9.0.0R4. A specially-crafted series of HTTP requests can lead to local file inclusion. An attacker can make a series of authenticated HTTP requests to trigger this vulnerability.

NVD Source

Technical Analysis

CVE-2021-21878 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires high privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), with a CVSS base score of 4.9.