CVE-2021-3166
An issue was discovered on ASUS DSL-N14U-B1 1.1.2.3_805 devices. An attacker can upload arbitrary...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
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.
- Record
CVE-2021-3166- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-434
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2021-3166- Updated
- 2026-11-02
EUVDEUVD-2021-26509 No score
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.
- Record
EUVD-2021-26509- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-mm32-fp7q-h532
An issue was discovered on ASUS DSL-N14U-B1 1.1.2.3_805 devices. An attacker can upload arbitrary...
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.
- Record
GHSA-mm32-fp7q-h532- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-434
- Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | kaisersource/CVE-2021-3166 | 2022-11-18 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-3166 is a high vulnerability (CVSS 7.5) in Asus Dsl-n14u B1 Firmware, published January 18, 2021. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 2.88%, the 86th percentile. No source names a fixed version.