HIGH

CVE-2021-3166

CVSS v3

7.5

HIGH

EPSS Score

2.9 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

Get an alert for each new CVE published for the software you run.

Set up CVE WatchFree account · no credit card

Affected and fixed versions

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2021-3166 yet.

Full record on NVD

Description

An issue was discovered on ASUS DSL-N14U-B1 1.1.2.3_805 devices. An attacker can upload arbitrary file content as a firmware update when the filename Settings_DSL-N14U-B1.trx is used. Once this file is loaded, shutdown measures on a wide range of services are triggered as if it were a real update, resulting in a persistent outage of those services.

Technical details

Published: 2021-01-18

Frequently asked questions

What is CVE-2021-3166?

Is CVE-2021-3166 actively exploited?

Active exploitation of CVE-2021-3166 has not been confirmed. Its EPSS score was 2.9% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-3166?

CVE-2021-3166 has a CVSS v3 base score of 7.5 (HIGH severity).

Hear about the next vulnerability in your software

CVE Watch matches each new CVE to the vendors and products you list (vendor and product, not the version) and puts it in your alerts with its KEV and EPSS status.

Get alerts for this product CISA KEV additions, October 2026 Search CVEs

Already have an account? Open CVE WatchNo credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Following what attackers exploit right now? The CISA KEV additions of the month, with their patch deadlines.
Running this software? CVE Watch alerts you to new vulnerabilities in your products.

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database