This vulnerability allows remote attackers to cause a denial-of-service condition on vulnerable installations of ZyXEL P-870H-51 DSL Router…

published 2018-02-21 8 y ago modified 2026-06-17 4 mo ago also EUVD-2018-11802

cvss: 9.8; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 4.0%; EPSS 4.0% chance of exploitation in 30 days, percentile 90%
public exploits: 0; none known

This vulnerability allows remote attackers to cause a denial-of-service condition on vulnerable installations of ZyXEL P-870H-51 DSL Router 1.00(AWG.3)D5. Authentication is not required to exploit this vulnerability. The specific flaw exists within numerous exposed CGI endpoints. The vulnerability is caused by improper access controls that allow access to critical functions without authentication. An attacker can use this vulnerability to reboot affected devices, along with other actions. Was ZDI-CAN-4540.

Exploit prediction

3.96% chance of exploitation in the next 30 days, higher than 90% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.0	9.8	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	10.0	AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected products

ZyXEL ZyXEL P-870H-51 DSL Router

Classification

Weakness

CWE-306 Missing Authentication for Critical Functionality
CWE-732 Incorrect Permission Assignment for Critical Resource

References

zerodayinitiative.com /advisories/ZDI-18-135
third-party-advisory, vdb-entry

Sources

CVE List CVE-2018-1164
NVD CVE-2018-1164

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Summary