Vulnerability in Mikrotik Routeros
CVE-2026-86060
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)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.064 (93.6th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 94th percentile — 93.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.064 · change: +0.053
Affected products
Weakness classification (CWE)
CISA KEV (Known Exploited Vulnerabilities)
This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.
BOD 22-01 due date: .
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.
Public proof-of-concept exploits
References
- cert.pl/en/posts/2026/09/mikrotik-routeros-cve (Third Party Advisory, third-party-advisory)
- cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploite… (technical-description, Third Party Advisory, Mitigation)
- forum.mikrotik.com/t/6-49-21-long-term-is-released/272802 (release-notes, Release Notes)
- forum.mikrotik.com/t/7-23-4-long-term-is-released/272801 (release-notes, Release Notes)
- forum.mikrotik.com/t/7-24-2-stable-is-released/272800 (release-notes, Release Notes)
- mikrotik.com/supportsec/september-2026-vulnerability/ (vendor-advisory, Vendor Advisory)
- npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-woul… (Exploit, Third Party Advisory, exploit)
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 (US Government Resource)
Frequently asked questions
- What is CVE-2026-86060?
- CVE-2026-86060 is a critical-severity vulnerability in Mikrotik Routeros, classified under Argument Injection. CVSS score: 9.8/10. Published 2026-09-05.
- How severe is CVE-2026-86060?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2026-86060 known to be exploited?
- Yes. CVE-2026-86060 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-09-10), indicating it is being actively exploited. 3 public proof-of-concept repositories are indexed.