CVE-2017-17537: MikroTik Routerboard

High severity, CVSS 7.5. EPSS: 1.8% chance of exploitation in the next 30 days.

MikroTik RouterBOARD v6.39.2 and v6.40.5 allows an unauthenticated remote attacker to cause a denial of service by connecting to TCP port 53 and sending data that begins with many '\0' characters, possibly related to DNS.

Affected products

• MikroTik Routerboard: version 6.39.2 only; version 6.40.5 only

Published 2017-12-13. Last modified 2026-09-16.