CVE-2017-18368: Zyxel P660HN-T1A Routers Command Injection Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 7 Aug 2023, 1,558 days after the CVE record was published.
- How likely is exploitation in the next 30 days?
- 94.5%
EPSS score, percentile 99.9 of all scored records
- How severe?
- 9.8 Critical
CVSS v3.1 base score, from CISA's enrichment of the record
- What should I do?
CISA deadline 28 Aug 2023. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Not stated. The CVE record gives vendor and product as “n/a” and the version as “unspecified”.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
What to do
Required action, set by CISA
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
CISA due date for this action: 28 August 2023.
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
Linked from CISA's catalog entry
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-a-new-variant-of-gafgyt-malware
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-command-injection-vulnerability-in-p660hn-t1a-dsl-cpe
- https://nvd.nist.gov/vuln/detail/CVE-2017-18368
Affected products and versions
The CVE record does not name affected products or versions: vendor and product are “n/a” and the version is “unspecified”.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
About this vulnerability
Zyxel P660HN-T1A routers contain a command injection vulnerability in the Remote System Log forwarding function, which is accessible by an unauthenticated user and exploited via the remote_host parameter of the ViewLog.asp page.
Summary: CISA's KEV catalog, as of 28 Oct 2026.
- CISA added CVE-2017-18368 to its Known Exploited Vulnerabilities (KEV) catalog on 7 Aug 2023.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 28 Aug 2023.
- The CVE record was published on 2 May 2019, 1,558 days before it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), taken from CISA's enrichment of the record.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 94.5% (percentile 99.9), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.
Description
The ZyXEL P660HN-T1A v1 TCLinux Fw $7.3.15.0 v001 / 3.40(ULM.0)b31 router distributed by TrueOnline has a command injection vulnerability in the Remote System Log forwarding function, which is accessible by an unauthenticated user. The vulnerability is in the ViewLog.asp page and can be exploited through the remote_host parameter.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
Weakness
- CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| 2 May 2019 | CVE record published |
| 7 Aug 2023 | Added to CISA KEV |
| 28 Aug 2023 | CISA due date for the required action |
| 21 Oct 2025 | CVE record last updated |
References
More exploited Zyxel vulnerabilities
- CVE-2026-7273: Zyxel GS1900 Series Switches Stack-Based Buffer Overflow Vulnerability
- CVE-2024-40890: Zyxel DSL CPE OS Command Injection Vulnerability
- CVE-2024-40891: Zyxel DSL CPE OS Command Injection Vulnerability
- CVE-2024-11667: Zyxel Multiple Firewalls Path Traversal Vulnerability
- CVE-2017-6884: Zyxel EMG2926 Routers Command Injection Vulnerability
- CVE-2023-27992: Zyxel Multiple NAS Devices Command Injection Vulnerability