CVE entry · CVE-2026-67277
CVE-2026-67277: MikroTik RouterOS Missing Authentication for Critical Function Vulnerability
MikroTik RouterOS contains a missing authentication for critical function vulnerability which allows kernel memory disclosure and denial of service in the btest service.
- Actively exploited: added to CISA’s KEV catalog on September 10, 2026.
- Use by ransomware: not established so far.
- Remediation deadline for US federal agencies: September 13, 2026.
Description from CISA’s KEV catalog.
What to do
- Check whether your estate includes MikroTik RouterOS, including internet-facing devices.
- Apply the vendor’s patch or mitigations (references below). Failing that, isolate the product or stop using it, as CISA requires of US federal agencies.
- An exploited vulnerability has often been used before it was fixed: look for signs of compromise, especially on internet-facing devices.