CVE-2026-86060
KEV: known exploited SSVC: activeSSH session privilege manipulation via a crafted username in Mikrotik RouterOS
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Attack conditions and impact
Derived from the NVD CVSS 3.1 vectorThis vulnerability may be exploitable over the internet without authentication or user interaction.
| Metric | Value | Meaning |
|---|---|---|
| Attack vector AV | N | Network |
| Attack complexity AC | L | Low (easy) |
| Privileges required PR | N | None |
| User interaction UI | N | None |
| Scope S | U | Unchanged |
| Confidentiality C | H | High |
| Integrity I | H | High |
| Availability A | H | High |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Description
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)
CISA KEV entry
MikroTik RouterOS Improper Neutralization of Argument Delimiters in a Command Vulnerability — MikroTik / RouterOS
MikroTik RouterOS contains an improper neutralization of argument delimiters in a command vulnerability which allows an attacker to change the trusted RouterOS policy mask, leading to privilege escalation.
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.
https://mikrotik.com/supportsec/september-2026-vulnerability ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-86060
CVSS assessments
| Provider | Version | Score | Vector |
|---|---|---|---|
| NVD / [email protected] (Secondary) | 4.0 | 9.2 CRITICAL | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD / [email protected] (Primary) | 3.1 | 9.8 CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA / CERT-PL | 4.0 | 9.2 CRITICAL | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
Affected products and packages
CNA (CVE.org)
| Vendor | Product | Versions |
|---|---|---|
| Mikrotik | RouterOS | affected: 7.24 … < 7.24.2 affected: 7.0.0 … < 7.23.4 affected: 6.0.0 … < 6.49.21 default: unaffected |
NVD CPE (3)
Show CPE list
| Vendor | Product | Range | CPE |
|---|---|---|---|
| mikrotik | routeros | >= 6.0, < 6.49.21 | cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:* |
| mikrotik | routeros | >= 7.0, < 7.23.4 | cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:* |
| mikrotik | routeros | >= 7.24, < 7.24.2 | cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:* |
Linux distribution status
References (8)
- https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve NVD, CNA Third Party Advisorythird-party-advisory
- https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/ NVD, CNA MitigationThird Party Advisorytechnical-description
- https://forum.mikrotik.com/t/6-49-21-long-term-is-released/272802 NVD, CNA Release Notesrelease-notes
- https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801 NVD, CNA Release Notesrelease-notes
- https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800 NVD, CNA Release Notesrelease-notes
- https://mikrotik.com/supportsec/september-2026-vulnerability/ NVD, CNA Vendor Advisoryvendor-advisory
- https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/ NVD, CNA ExploitThird Party Advisoryexploit
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-86060 NVD, ADP CISA-ADP US Government Resourcegovernment-resource