CVE-2026-86060

SSH session privilege manipulation via a crafted username in Mikrotik RouterOS

CRITICAL

9.8

CVSS Score

Published: September 5, 2026 at 08:00 PM UTC

Updated: September 11, 2026 at 01:10 PM UTC

1 product affected across 1 vendorRouterOS

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Severity

CRITICAL9.8

Exploitation

CISA KEV

Exploit prediction

EPSS 6%

SSVC

Active

Actively Exploited

CISA Known Exploited Vulnerabilities (KEV) Catalog

EPSS Score6.4%

EPSS (Exploit Prediction Scoring System) estimates a 6.4% chance this CVE is exploited in the wild within the next 30 days — higher than 94% of all CVEs. It complements CVSS: a high EPSS on a mid-severity CVE can still be urgent.

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.

Ransomware Use

Unknown

Added to KEV

Sep 10, 2026

Remediation Due

Sep 13, 2026

49 days overdue

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

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 (Lont-term), 7.23.4 (Lont-term) and 7.24.2 (Stable)