Emerging Threat: (CVE-2026-84411) MikroTik RouterOS Unauthenticated Root RCE via Web Management
CVE-2026-84411 is an integer underflow in the web management service of MikroTik RouterOS, classified as CWE-191. The flaw sits in the service’s HTTP request body handling and is reachable before authentication. A single crafted request lets an unauthenticated network attacker execute arbitrary code as root, or crash the device. The vulnerability carries a CVSS v3.1 base score of 9.8 (Critical) and a CVSS v4.0 base score of 9.3 (Critical).