CVE-2026-67279

MediumActively exploited (CISA KEV)

Description

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)

SeverityMedium
CVSS6.5
Exploit probability—
ProductMikroTik RouterOS
PublishedSep 5, 2026
First seenSep 5, 2026
Added to KEVSep 25, 2026
Weakness typeCWE-841CWE-841

How to fix

CISA required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

CISA due date: Sep 28, 2026
Update
  • mikrotik routeros6.49.21, 7.23.4, 7.24.2 or later

Affected products

ProductAffected versionsFixed in
mikrotik routeros6.0 ≤ v < 6.49.21, 7.0 ≤ v < 7.23.4, 7.24 ≤ v < 7.24.26.49.21, 7.23.4, 7.24.2

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