PatchTheCVECVE-2017-18368: Zyxel P660HN-T1A Routers Command Injection Vulnerability
CVE-2017-18368 is a critical-severity flaw (CVSS 9.8) affecting 5200w-t firmware, p660hn-t1a v2 firmware, p660hn-t1a v1 firmware, reported as exploited in the wild. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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.
Why this priority
- Critical severity
- EPSS top 1%: very likely to be exploited
- Exploited in the wild (CISA KEV)
- Public exploit reference
- CISA SSVC: automatable with total technical impact
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 94.5% (top 1%) |
| CISA exploited list | Yes, fix due 2023-08-28 |
| Weakness | CWE-78 |
| Published | 2019-05-02 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Exploited Added to the CISA Known Exploited Vulnerabilities list
- Deadline CISA due date for US federal agencies to patch
- Updated Record last modified
Exact fixes by distribution
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- Write-up: raw.githubusercontent.com/pedrib/PoC/master/advisories/zyxel_trueonline.txt
- Write-up: seclists.org/fulldisclosure/2017/Jan/40
- Write-up: ssd-disclosure.com/index.php/archives/2910
- Metasploit: TrueOnline / ZyXEL P660HN-T v1 Router Unauthenticated Command Injection
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2017-18368?
5200w-t firmware: mitigate or apply the listed mitigation; p660hn-t1a v2 firmware: mitigate or apply the listed mitigation; p660hn-t1a v1 firmware: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2017-18368 being exploited?
Yes. CVE-2017-18368 is on the CISA Known Exploited Vulnerabilities list, so treat it as patch-now.
What does CVE-2017-18368 affect?
CVE-2017-18368 affects 5200w-t firmware, p660hn-t1a v2 firmware, p660hn-t1a v1 firmware. Severity is critical (CVSS 9.8). 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 vuln
How urgent is CVE-2017-18368?
Priority 97/100. Critical severity; EPSS top 1%: very likely to be exploited; Exploited in the wild (CISA KEV); Public exploit reference; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action
Software pages
Related CVEs
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