The ZyXEL P660HN-T1A v2 TCLinux Fw #7.3.37.6 router distributed by TrueOnline has three user accounts with default passwords, including two hardcoded service accounts: one with the username true and password true, and another with the username supervisor and password zyad1234. These accounts can be used to login to the web interface, exploit authenticated command injections, and change router settings for malicious purposes.
Conclusion & alert: CVE-2017-18371 is rated High Exploit Risk (88.2/100): CVSS Critical severity, with high exploitation likelihood (EPSS 72.74%, 99th percentile). Core evidence: 3 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ | |
| — | nvd_ref | exploit_tag | Exploit-DB ↗ | |
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-04-02 | 73.28% | 72.74% | -0.54% |
| 2 | 2026-02-15 | 73.55% | 73.28% | -0.27% |
| 3 | 2025-11-18 | — | 73.55% | — |
Full EPSS history (16 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.8 | 3.0 | CRITICAL |
|
3.9 | 5.9 | [email protected] |
| 7.5 | 2.0 | HIGH |
|
10.0 | 6.4 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| billion | 5200w-t_firmware | 7.3.8.0 | cpe:2.3:o:billion:5200w-t_firmware:7.3.8.0:*:*:*:*:*:*:* |
| zyxel | p660hn-t1a_v2_firmware | 7.3.37.6 | cpe:2.3:o:zyxel:p660hn-t1a_v2_firmware:7.3.37.6:*:*:*:*:*:*:* |
| zyxel | p660hn-t1a_v1_firmware | 7.3.37.6 | cpe:2.3:o:zyxel:p660hn-t1a_v1_firmware:7.3.37.6:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| http://www.zyxel.com/support/announcement_unauthenticated.shtml | Broken Link |
| https://raw.githubusercontent.com/pedrib/PoC/master/advisories/zyxel_trueonline.txt | Exploit Third Party Advisory |
| https://seclists.org/fulldisclosure/2017/Jan/40 | Exploit Mailing List Third Party Advisory |
| https://ssd-disclosure.com/index.php/archives/2910 | Exploit Technical Description Third Party Advisory |
| https://unit42.paloaltonetworks.com/new-mirai-variant-targets-enterprise-wireless-presentation-display-systems/ | Technical Description Third Party Advisory |