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CVE-2026-16347 (GCVE-0-2026-16347)

Vulnerability from cvelistv5 – Published: 2026-07-28 19:59 – Updated: 2026-07-29 13:57
VLAI
Title
Improper restriction of excessive authentication attempts in MikroTik RouterOS and Cloud Hosted Router
Summary
MikroTik RouterOS contains a weakness in its API authentication handling that lacks effective safeguards against excessive login attempts. The system does not enforce meaningful rate-limiting, account lockout, or source-based restrictions, allowing repeated authentication failures to proceed without defensive response. In some versions, a fixed per-connection delay is present, but it can be bypassed through concurrent sessions, resulting in continued high-volume attempts. This deficiency increases the risk that an attacker could eventually obtain valid credentials and gain unauthorized access to administrative services.
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-29 13:57 UTC
CWE
  • CWE-307 - Improper restriction of excessive authentication attempts
References
Impacted products
Vendor Product Version CPE status
MikroTik RouterOS Affected: All versions
guessed Create a notification for this product.
MikroTik Cloud Hosted Router Affected: All versions
guessed Create a notification for this product.
Show details on NVD website

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