CVE-2017-18374
The ZyXEL P660HN-T1A v1 TCLinux Fw $7.3.15.0 v001 / 3.40(ULM.0)b31 router distributed by...
The ZyXEL P660HN-T1A v1 TCLinux Fw $7.3.15.0 v001 / 3.40(ULM.0)b31 router distributed by TrueOnline has two user accounts with default passwords, including a hardcoded service account with the username true and password true. These accounts can be used to login to the web interface, exploit authenticated command injections and change router settings for malicious purposes.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
8.8
The ZyXEL P660HN-T1A v1 TCLinux Fw $7.3.15.0 v001 / 3.40(ULM.0)b31 router distributed by TrueOnline has two user accounts with default passwords, including a hardcoded service account with the username true and password true. These accounts can be used to login to the web interface, exploit authenticated command injections and change router settings for malicious purposes.
- Record
CVE-2017-18374- CVSS 3.0
- 8.8 High
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 9.0 High
AV:N/AC:L/Au:S/C:C/I:C/A:C - Weakness
- CWE-798
- Updated
- 2026-11-02
CVE List No score
The ZyXEL P660HN-T1A v1 TCLinux Fw $7.3.15.0 v001 / 3.40(ULM.0)b31 router distributed by TrueOnline has two user accounts with default passwords, including a hardcoded service account with the username true and password true. These accounts can be used to login to the web interface, exploit authenticated command injections and change router settings for malicious purposes.
- Record
CVE-2017-18374- Updated
- 2026-11-02
EUVDEUVD-2017-9490 No score
The ZyXEL P660HN-T1A v1 TCLinux Fw $7.3.15.0 v001 / 3.40(ULM.0)b31 router distributed by TrueOnline has two user accounts with default passwords, including a hardcoded service account with the username true and password true. These accounts can be used to login to the web interface, exploit authenticated command injections and change router settings for malicious purposes.
- Record
EUVD-2017-9490- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-3r7r-mrpq-cx9g
8.8
The ZyXEL P660HN-T1A v1 TCLinux Fw $7.3.15.0 v001 / 3.40(ULM.0)b31 router distributed by...
The ZyXEL P660HN-T1A v1 TCLinux Fw $7.3.15.0 v001 / 3.40(ULM.0)b31 router distributed by TrueOnline has two user accounts with default passwords, including a hardcoded service account with the username true and password true. These accounts can be used to login to the web interface, exploit authenticated command injections and change router settings for malicious purposes.
- Record
GHSA-3r7r-mrpq-cx9g- CVSS 3.0
- 8.8 High
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-798
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2017-18374 is a high vulnerability (CVSS 8.8) in Billion 5200w-t Firmware, published May 2, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 5.50%, the 92nd percentile. No source names a fixed version.
References
seclists.org/fulldisclosure/2017/Jan/40
ssd-disclosure.com/index.php/archives/2910
unit42.paloaltonetworks.com/new-mirai-variant-targets-enterprise-wireless-presentation-display-systems
raw.githubusercontent.com/pedrib/PoC/master/advisories/zyxel_trueonline.txt
zyxel.com/support/announcement_unauthenticated.shtml
nvd.nist.gov/vuln/detail/CVE-2017-18374
github.com/advisories/GHSA-3r7r-mrpq-cx9g