CVEs / CVE-2026-67279
CVE-2026-67279: Mikrotik RouterOS Improper Enforcement of Behavioral Workflow Vulnerability
- Known exploited in the CISA KEV catalog since 25 Sep 2026
- medium 6.5 CVSS 3.1 (NVD)
- EPSS 2.27% chance of exploitation in the next 30 days, higher than 83% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
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)
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Mikrotik RouterOS | from 7.24, before 7.24.2 | 7.24.2 |
| Mikrotik RouterOS | from 7.0.0, before 7.23.4 | 7.23.4 |
| Mikrotik RouterOS | from 6.0.0, before 6.49.21 | 6.49.21 |
Exploitation
| In CISA KEV since | 25 Sep 2026 |
|---|---|
| Due date for US federal agencies | 28 Sep 2026 |
| Used in ransomware campaigns | Unknown |
| 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. |
Severity
| CVSS 3.1 | 6.5 mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NScored by NVD |
|---|---|
| Weakness | CWE-841 |
References
- CVE-2026-67279 on NVD
- CVE-2026-67279 in the CISA KEV catalog
- https://mikrotik.com/supportsec/september-2026-vulnerability (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk (cited by CISA)
- https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve Third Party Advisory
- https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/ Mitigation, Third Party Advisory
- https://forum.mikrotik.com/t/6-49-21-long-term-is-released/272802 Release Notes
- https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801 Release Notes
- https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800 Release Notes
- https://mikrotik.com/supportsec/september-2026-vulnerability/ Vendor Advisory
- https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/ Exploit, Third Party Advisory
- https://bishopfox.com/blog/mikrotrick-inside-the-routeros-takeover-chain Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-67279 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.