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

published 2021-01-18 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-26509

cvss: 7.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 2.9%; EPSS 2.9% chance of exploitation in 30 days, percentile 86%
public exploits: 0; none known

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.

Exploit prediction

2.88% chance of exploitation in the next 30 days, higher than 86% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

kaisersource.github.io https://kaisersource.github.io/dsl-n14u referenced PoC, tagged "exploit" by a source, unverified
github.com https://github.com/kaisersource/kaisersource.github.io/blob/main/_posts/2021-01-17-dsl-n14u.md referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Classification

Weakness

CWE-434 Unrestricted Upload of File with Dangerous Type

References

kaisersource.github.io /dsl-n14u
exploit, third-party-advisory
github.com /kaisersource/kaisersource.github.io/blob/main/_posts/2021-01-17-dsl-n14u.md
exploit, third-party-advisory

Sources

CVE List CVE-2021-3166
NVD CVE-2021-3166

Fencer Vulns 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.

Summary