CVEvulnerability

CVE-2026-86060

9.2 CRITICAL Known exploited Published 2026-09-05 Modified 2026-09-11 Official page ↗

CISA Known Exploited Vulnerability

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.

Added to KEV: 2026-09-10
Remediation due: 2026-09-13
Ransomware use: 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.
Notes: 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

Status: Analyzed
Published: 2026-09-05
Last modified: 2026-09-11
Assigner: [email protected]
CVSS 4.0 ([email protected]): 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
CVSS 3.1 ([email protected]): 9.8 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weaknesses: CWE-88

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)

Affected configurations

• mikrotik routeros (>= 6.0 < 6.49.21) • mikrotik routeros (>= 7.0 < 7.23.4) • mikrotik routeros (>= 7.24 < 7.24.2)

Weakness · CWE (1)

CWE-88 Improper Neutralization of Argument Delimiters in a Command weakness

References