SSH session privilege manipulation via a crafted username in Mikrotik RouterOS (Mikrotik RouterOS)
At a glance
- Source
- NVD
- EPSS
- EPSS 6.39 % · percentile 94 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- CERT-PL
- NVD status
- Analyzed
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)
Weaknesses (CWE)
- CWE-88 — Improper Neutralization of Argument Delimiters in a Command
References
- https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve
- https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/
- https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/
- https://mikrotik.com/supportsec/september-2026-vulnerability/
- https://forum.mikrotik.com/t/6-49-21-long-term-is-released/272802
- https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801
- https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-86060
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 4.0 | CRITICAL 9.2 | 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 | CERT-PL |
| CVSS 4.0 | CRITICAL 9.2 | 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 · cvd@cert.pl (Secondary) |
| CVSS 3.1 | CRITICAL 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | NVD · nvd@nist.gov (Primary) |
European references
- ENISA EUVD · EUVD-2026-72029
- GCVE · GCVE-0-2026-86060
Affected configurations (NVD CPE)
cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*≥ 6.0 < 6.49.21cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*≥ 7.0 < 7.23.4cpe:2.3:o:mikrotik:routeros:*:*:*:*:*:*:*:*≥ 7.24 < 7.24.2
Affected products
| Product | Versions |
|---|---|
| Mikrotik · RouterOS | affected 7.24 < 7.24.2 ; affected 7.0.0 < 7.23.4 ; affected 6.0.0 < 6.49.21 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| CISA Known Exploited Vulnerabilities | CC0 1.0 |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |