CVE-2017-6884
Zyxel EMG2926 Routers Command Injection Vulnerability
Zyxel EMG2926 Routers
A command injection vulnerability was discovered on the Zyxel EMG2926 home router with firmware V1.00(AAQT.4)b8. The vulnerability is located in the diagnostic tools, specifically the nslookup function. A malicious user may exploit numerous vectors to execute arbitrary commands on the router, such as the ping_ip parameter to the expert/maintenance/diagnostic/nslookup URI.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 18 September 2023. US federal agencies were required to remediate it by 9 October 2023. CISA records this vulnerability as known to be used in ransomware campaigns.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 34.6%, which is higher than 98.4% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2017-6884 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2017-6884.
What does CVE-2017-6884 affect?
CVE-2017-6884 affects Zyxel EMG2926 Routers. A command injection vulnerability was discovered on the Zyxel EMG2926 home router with firmware V1.00(AAQT.4)b8. The vulnerability is located in the diagnostic tools, specifically the nslookup function. A malicious user may exploit numerous vectors to execute arbitrary commands on the router, such as the ping_ip parameter to the expert/maintenance/diagnostic/nslookup URI.
How severe is CVE-2017-6884?
CVE-2017-6884 is rated HIGH with a CVSS base score of 8.8. EPSS puts the probability of exploitation in the next 30 days at 34.6%, higher than 98.4% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 9 October 2023.
How should organisations respond to CVE-2017-6884?
Apply the vendor patch for Zyxel EMG2926 Routers as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.