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
Why It Matters
Analysis dossierWhy It Matters
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)
Immediate Attention
Yes
Unknown
Risk basis: CISA KEV exploitation signal; Known exploitation signal from CISA KEV or ransomware metadata
Affected Products & Remediation
1 source-backed product- mikrotik routeros · >= 6.0 < 6.49.21; >= 7.0 < 7.23.4; >= 7.24 < 7.24.2 · NVD CPE · Source
Vendor or catalog guidance (source)
- CISA KEV: 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.
Known exploitation (source facts)
Only what a source states. Unknown means no source has said either way; it is not "not exploited".
- CISA KEV
- Listed
- Exploited (source statement)
- Yes
- Publicly disclosed (source)
- Unknown
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.
Suggested hunting (rule-based inference)
SecOps Signal recommendation (rule-based inference). These steps are hunting hypotheses from the vulnerability class; they do not state or imply that exploitation occurred here or anywhere.
Matched kev-network-exposure (CVSS AV:N, CISA KEV Listed); network-unauthenticated (CVSS AV:N, CVSS PR:N, CVSS UI:N)
Exposure
- Identify assets with the exact CVE and confirm the affected product/version against the advisory.Telemetry: DeviceTvmSoftwareVulnerabilities · KEV listing raises urgency, but inventory is needed to establish local exposure. · Rule kev-network-exposure
- Identify devices reporting this CVE and note which expose the affected service to untrusted networks.Telemetry: DeviceTvmSoftwareVulnerabilities · A network-reachable, no-privilege vector makes internet-facing instances the first exposure question. · Rule network-unauthenticated
Exploitation evidence
- Review relevant edge or application access logs for unusual requests around the advisory window.Telemetry: CommonSecurityLog · Log review is a hunting hypothesis; KEV listing alone does not show local exploitation. · Rule kev-network-exposure
Show more (2)
Exploitation evidence
- Review inbound connections to the affected service from unexpected sources since the advisory date.Telemetry: DeviceNetworkEvents · Hunting hypothesis from the CVSS vector; it does not show that exploitation occurred. · Rule network-unauthenticated
Response
- Recheck the affected assets after the source-stated mitigation or update is applied.Telemetry: DeviceTvmSoftwareVulnerabilities · A follow-up inventory check verifies local remediation. · Rule kev-network-exposure
CISA KEV Record
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.
Change History & Source Data
— No recorded material change
- CNA / source
- cvd@cert.pl
- Record status · verification
- NEW · CISA KEV confirmed
- CPE
- cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*
Evidence & Provenance
Linked by the query's stored exact CVE association. Review required tables and validation status before use.
DeviceTvmSoftwareVulnerabilities| where CveId == "CVE-2026-67279"| project DeviceId, DeviceName, OSPlatform, OSVersion, SoftwareVendor, SoftwareName, SoftwareVersion, CveId, VulnerabilitySeverityLevel, RecommendedSecurityUpdate, RecommendedSecurityUpdateId| sort by VulnerabilitySeverityLevel descCorrelated briefings
— No published briefing references this CVE