CVE-2026-86060: MikroTik RouterOS Improper Neutralization of Argument Delimiters in a Command Vulnerability

What it is

RouterOS contains an argument-handling flaw in the SSH login path involving usernames that begin with a prohibited character, allowing for the trusted RouterOS policy mask to be changed, leading to privilege escalation. Exploitation requires an unauthenticated SSH session to reach the RouterOS login helper.This issue was fixed in versions: 6.49.21 (Long-term), 7.23.4 (Long-term) and 7.24.2 (Stable)

Exploitation evidence

First exploit evidence seen: 2026-09-10 (earliest date across the sources below).

Exploited in the wild

• CISA KEV: listed since 2026-09-10. Source

Public exploit code

Exploit-DB

• EDB-52683: MikroTrick_ 7.24_ 7.24.2_ 7.0.0_ 7.23.4_ 6.0.0_ 6.49.21 - RCE (2026-09-24)

GitHub proof-of-concept repositories

3 public repositories from 3 accounts, first seen 2026-09-10. Most starred: digiprosec/MicroTrick (55 stars), view repository.

Verify before running: public PoCs can be malicious. Read the code and only run it in an isolated lab. A PoC means exploit code is public, not that this CVE is exploited in the wild.

Sources: CISA KEV · Exploit-DB (OffSec) · nomi-sec/PoC-in-GitHub.

How to fix it

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. (source: CISA KEV)

Fixed versions

• mikrotik routeros: upgrade to 6.49.21 or later (affected from 6.0)
• mikrotik routeros: upgrade to 7.23.4 or later (affected from 7.0)
• mikrotik routeros: upgrade to 7.24.2 or later (affected from 7.24)

Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.

Vendor advisories and patches

• https://mikrotik.com/supportsec/september-2026-vulnerability (CISA KEV notes)
• 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)

MITRE ATT&CK mitigations for this chain

• M1051 Update Software (for T1068) : Update software regularly by employing patch management for internal enterprise endpoints and servers.
• M1050 Exploit Protection (for T1068) : Security applications that look for behavior used during exploitation such as Windows Defender Exploit Guard (WDEG) and the Enhanced Mitigation Experience Toolkit (EMET) can be used to mitigate some exploitation behavior. Control flow integrity checking is another way to potentially identify and stop a software exploi
• M1048 Application Isolation and Sandboxing (for T1068) : Make it difficult for adversaries to advance their operation through exploitation of undiscovered or unpatched vulnerabilities by using sandboxing. Other types of virtualization and application microsegmentation may also mitigate the impact of some types of exploitation. Risks of additional exploits and weaknesses in t
• M1019 Threat Intelligence Program (for T1068) : Develop a robust cyber threat intelligence capability to determine what types and levels of threat may use software exploits and 0-days against a particular organization.
• M1038 Execution Prevention (for T1068) : Consider blocking the execution of known vulnerable drivers that adversaries may exploit to execute code in kernel mode. Validate driver block rules in audit mode to ensure stability prior to production deployment.

Detection Generic guidance

• Privilege Escalation: Alert on processes gaining SYSTEM/root unexpectedly, and on exploitation crashes of privileged services.

Response checklist Generic guidance

1. Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
2. Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
3. Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
4. Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.