CVE-2026-67277

CVE CVE-2026-67277EUVD EUVD-2026-72025Published 2026-09-05T20:00:56.000ZLast changed 2026-09-11T03:55:58.000ZCVSS 8.8

Listed by CISA as actively exploited CISA added this vulnerability to its catalogue of known exploited vulnerabilities on 2026-09-10. That means attacks against it have been observed.

What the advisory describes

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)

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

MikroTik — RouterOS 7.0.0 <7.23.4; 7.24 <7.24.2; 6.0.0 <6.49.21

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

MikroTik — RouterOS

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