CVE-2026-86060

Published Sep 5, 2026

Last updated a month ago

Exploit known CVSS critical 9.2

SSH

Dns

Tunneling protocol

Firmware

RouterOS

Overview

AI description

Automated description summarized from trusted sources.

CVE-2026-86060 is an argument-handling flaw identified in MikroTik RouterOS, specifically within its SSH login path. This vulnerability arises when usernames begin with a prohibited character, which can be manipulated to alter the trusted RouterOS policy mask. Such a change ultimately leads to privilege escalation within the system. Exploitation of CVE-2026-86060 requires an unauthenticated SSH session to successfully reach the RouterOS login helper. This flaw is often discussed in conjunction with CVE-2026-67276, an SSH authentication bypass, as chaining these two vulnerabilities can allow an attacker to gain full, unauthenticated control over affected MikroTik devices. MikroTik has released fixes for this issue in RouterOS versions 6.49.21 (Long-term), 7.23.4 (Long-term), and 7.24.2 (Stable).

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)
Source: cvd@cert.pl
NVD status: Analyzed
Products: routeros

Risk scores

CVSS 4.0

Type: Secondary
Base score: 9.2
Impact score: -
Exploitability score: -
Vector string: 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
Severity: CRITICAL

CVSS 3.1

Type: Primary
Base score: 9.8
Impact score: 5.9
Exploitability score: 3.9
Vector string: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: CRITICAL

Known exploits

Data from CISA

Vulnerability name: MikroTik RouterOS Improper Neutralization of Argument Delimiters in a Command Vulnerability
Exploit added on: Sep 10, 2026
Exploit action due: Sep 13, 2026
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.

Weaknesses

cvd@cert.pl: CWE-88

Hype score: Not currently trending

Configurations

[
  {
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*",
            "matchCriteriaId": "CFC981EC-B44C-40B5-945B-2283FADEC961",
            "versionEndExcluding": "6.49.21",
            "versionStartIncluding": "6.0",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*",
            "matchCriteriaId": "881306AB-32B1-4B5F-96D8-9532D25F7AE4",
            "versionEndExcluding": "7.23.4",
            "versionStartIncluding": "7.0",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*",
            "matchCriteriaId": "A41D6B3C-D321-4C61-B3D5-00F8276CB4AC",
            "versionEndExcluding": "7.24.2",
            "versionStartIncluding": "7.24",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ]
  }
]

References

Sources include official advisories and independent security research.