CVE-2026-67277

Kernel memory disclosure and denial of service in MikroTik RouterOS btest service

CVSS 8.8 high · Mikrotik RouterOS · published 2026-09-05

RouterOS accepts a "related" btest connection before the corresponding primary session has completed authentication. An unauthenticated client can use this state to start an IPv4 UDP test. With "random-data=false", the sender transmits an uninitialized tail from a kernel packet buffer. A separate unchecked, inverted packet-size interval causes unsigned integer underflow, anomalously large fragmented output, and can restart the RouterOS kernel. This issue was fixed in versions: 6.49.21 (Long-term), 7.23.4 (Long-term) and 7.24.2 (Stable)

NVD · CVE.org

Coverage 1 source

1. 2026-09-10 CISA Cybersecurity Advisories high CISA Adds Two Known Exploited Vulnerabilities to Catalog

   CISA added two MikroTik RouterOS vulnerabilities to its Known Exploited Vulnerabilities Catalog.

Mentioned with

CVE-2026-86060

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