: Attackers could modify a single byte in a Session ID request to the Winbox server on port 8291.
Understanding MikroTik RouterOS Authentication Bypass Vulnerabilities
(Adjust the src-address to match your trusted LAN subnet).
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This public link is valid for 7 days and shares a thread, including any personal information you added. This link or copies made by others cannot be deleted. If you share with third parties, their policies apply. Can’t copy the link right now. Try again later. mikrotik routeros authentication bypass vulnerability
Create a firewall rule ( IP -> Firewall -> Filter ) that only allows known, trusted IP addresses to access port 8291 (WinBox) or 80/443 (WebFig).
Unbeknownst to them, a flaw exists in the RouterOS’s WebFig interface (CVE-2026-XXXX, fictional). A specially crafted HTTP POST request to /login with a null byte in the username field ( admin%00 ) bypasses password verification entirely. No logs are generated because the authentication routine crashes before writing the entry.
: Disable unused services (IP -> Services).
New RouterOS Vulnerability? - General - MikroTik community forum : Attackers could modify a single byte in
Understanding and Mitigating MikroTik RouterOS Authentication Bypass Vulnerabilities
The vulnerability can be exploited by a remote authenticated user with "admin" privileges on the vulnerable device. Once escalated to super-admin, the attacker gains full remote control of the router, enabling them to:
More recently, was identified as a critical vulnerability (CVSS 10.0) affecting MikroTik RouterOS (up to version 7.14.2) through the WebFig management interface. The issue stems from insecure default configurations where WebFig initializes with HTTP enabled and without redirection to HTTPS. After a factory reset, the entire management interface loads over cleartext HTTP, exposing credentials during authentication. On-path attackers can intercept and modify management traffic through Man-in-the-Middle (MITM) attacks.
This is the most notorious authentication bypass in MikroTik's history, allowing unauthenticated attackers to read arbitrary files, including the user database. 10.0 (Critical) This link or copies made by others cannot be deleted
Create a new administrator account with a unique name and delete or disable the default account named "admin". 4. Implement Firewall Rules
The Silent Night Shift
: Briefly describe the critical nature of MikroTik devices in global infrastructure. State that this paper analyzes how flaws in proprietary protocols (like Winbox) or system management interfaces allow unauthenticated attackers to gain unauthorized access.