---
id: CVE-2026-67279
title: >-
  RouterOS SSH enters the connection protocol after a client-requested rekey
  even though user authentication was never attempted, allowing an
  unauthenticated client to open a session channel and send an exec request
summary: >-
  RouterOS SSH enters the connection protocol after a client-requested rekey
  even though user authentication was never attempted, allowing an
  unauthenticated client to open a session channel and send an exec request. On
  affected builds the…
severity: medium
cvss: 6.9
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-841
vendor: Mikrotik
product: RouterOS
affected:
  - RouterOS >= 7.24 < 7.24.2
  - RouterOS >= 7.0.0 < 7.23.4
  - RouterOS >= 6.0.0 < 6.49.21
published: '2026-09-05'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T16:18:10.600'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67279'
references:
  - url: 'https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve'
    label: cvd@cert.pl
  - url: >-
      https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/
    label: cvd@cert.pl
  - url: 'https://forum.mikrotik.com/t/6-49-21-long-term-is-released/272802'
    label: cvd@cert.pl
  - url: 'https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801'
    label: cvd@cert.pl
  - url: 'https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800'
    label: cvd@cert.pl
  - url: 'https://mikrotik.com/supportsec/september-2026-vulnerability/'
    label: cvd@cert.pl
  - url: >-
      https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/
    label: cvd@cert.pl
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-08T15:31:15.958392Z'
cvssSource: cna
epss: 0.00446
epssPercentile: 0.38028
ingestedAt: '2026-09-06T10:53:52.466Z'
---

## Overview

RouterOS SSH enters the connection protocol after a client-requested rekey even though user authentication was never attempted, allowing an unauthenticated client to open a session channel and send an exec request. On affected builds the server dispatches the command, enabling unauthenticated creation, overwrite, and reconstruction of files in the RouterOS managed file namespace, including support files containing configuration and diagnostic data.This issue was fixed in versions: 6.49.21 (Long-term), 7.23.4 (Long-term) and 7.24.2 (Stable)

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.