CVE-2026-67277 Mikrotik — Exploit & Vulnerability Details HIGH

Parameter	Value
CVSS	8.8 (HIGH)
Affected Versions	0.0.0 — 7.25.1
Fixed In	7.25.1
Type	CWE-306 (Missing Authentication for Critical Function)
Vendor	Mikrotik
Public PoC	Yes

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)

Attack Parameters

Attack Vector

Network

Can be exploited remotely

Attack Complexity

Low

Easy to exploit

Attack Requirements

None

No additional conditions

Privileges Required

None

No privileges needed

User Interaction

None

No user interaction needed

Impact Assessment

Confidentiality

Low

Partial data leak

Integrity

None

No data modification

Availability

High

Complete denial of service

CVSS Vector v4.0

Weakness Type (CWE)

CWE-306 Missing Authentication for Critical Function

Vulnerable Products 4

Configuration	From (including)	Up to (excluding)
Mikrotik Routeros cpe:2.3:a:mikrotik:routeros::::::::	`0.0.0`	`7.25.1`
Mikrotik Routeros cpe:2.3:o:mikrotik:routeros::::::::	`6.0`	`6.49.21`
Mikrotik Routeros cpe:2.3:o:mikrotik:routeros::::::::	`7.0`	`7.23.4`
Mikrotik Routeros cpe:2.3:o:mikrotik:routeros::::::::	`7.24`	`7.24.2`