CVE-2021-3166

7.5 HIGH

An issue was discovered on ASUS DSL-N14U-B1 1.1.2.3_805 devices

Published: 2021-01-18 · Last updated: 2026-06-17

Severity and scoring

CVSS: 7.5 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: CWE-434

Affected products

Vendor	Product
asus	dsl-n14u_b1_firmware

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.

Source: NVD

References

[NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-3166
[Exploit reference]https://github.com/kaisersource/kaisersource.github.io/blob/main/_posts/2021-01-17-dsl-n14u.md
[Exploit reference]https://kaisersource.github.io/dsl-n14u
[Exploit reference]https://github.com/kaisersource/kaisersource.github.io/blob/main/_posts/2021-01-17-dsl-n14u.md
[Exploit reference]https://kaisersource.github.io/dsl-n14u

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