CVE-2026-67279
Mikrotik RouterOS Improper Enforcement of Behavioral Workflow Vulnerability
Published Sep 5, 2026 · updated Sep 25, 2026 · MikroTik RouterOS
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)
Timeline
Detection, updates, and resolution for this record.
Sep 5, 2026 · Catalog
Detected
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
Sep 25, 2026 · CISA KEV
Known exploited
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
Sep 25, 2026 · Catalog
Updated
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
Sep 28, 2026 · CISA KEV
Remediation due
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
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
Affected
- cpe mikrotik/routerosversion unspecified
- vendor MikroTik RouterOSversion unspecified
Sources
- CISA KEVCVE-2026-67279
Mikrotik RouterOS contains an improper enforcement of behavioral workflow vulnerability that could allow an unauthenticated client to open a session channel and send an exec request. This vulnerability can be chained to achieve unauthenticated exploitation of CVE-2026-86060.
cisa.gov - CVE.orgCVE-2026-67279
Official CVE identifier
cve.org - FIRST EPSSCVE-2026-67279
30-day exploitation probability 1.0%
first.org - NIST NVDCVE-2026-67279
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 un
nvd.nist.gov
References
- Third Party Advisory · bishopfox.com
- Third Party Advisory · cert.pl
- Mitigation · cert.pl
- Release Notes · forum.mikrotik.com
- Release Notes · forum.mikrotik.com
- Release Notes · forum.mikrotik.com
- Vendor Advisory · mikrotik.com
- CISA note · mikrotik.com
- Exploit · npratley.net
- CISA note · nvd.nist.gov
- CISA note · cisa.gov
- CISA note · cisa.gov