CVE-2026-67277 MikroTik RouterOS: login or permission bypass
In plain words: A door that should be locked is not: part of the system can be reached without a valid login or permission. The attacker gets in as a user or administrator without knowing a password.
Confirmed exploited by CISA on · US federal patch deadline Sep 13, 2026
What to do
- Install MikroTik's security update for RouterOS. If no update exists, follow the vendor's workaround or stop using the product until one ships.
- Turn on automatic firmware updates and replace gear the maker no longer supports.
- Change default passwords and switch off remote administration and features you do not use.
- Do not put storage boxes or cameras directly on the internet — use the maker's app or a VPN.
Who is affected
Could reach you. This one is aimed at devices or apps of the kind people own.
What's at risk: Taken over in bulk to join botnets, used to watch your traffic, or — for storage boxes — locked by ransomware.
The details
- Official name
- MikroTik RouterOS Missing Authentication for Critical Function Vulnerability
- Product
- MikroTik RouterOS
- CISA description
- MikroTik RouterOS contains a missing authentication for critical function vulnerability which allows kernel memory disclosure and denial of service in the btest service.
- Type of flaw
- Login or permission bypass (CWE-306)
- Confirmed exploited
- Sep 10, 2026
- US federal patch deadline
- Sep 13, 2026
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Answering about CVE-2026-67277 ·
Questions about CVE-2026-67277
Is CVE-2026-67277 being exploited?
Yes. CISA added CVE-2026-67277 to its Known Exploited Vulnerabilities catalog on Sep 10, 2026, which means there is reliable evidence of real-world attacks.
How do I fix CVE-2026-67277?
Install MikroTik's security update for RouterOS. If no update exists, follow the vendor's workaround or stop using the product until one ships. Turn on automatic firmware updates and replace gear the maker no longer supports.
Am I affected by CVE-2026-67277?
Only if you use MikroTik RouterOS. This one is aimed at devices or apps of the kind people own.