Patchfirst
CVE-2026-67279 KEVPublic exploit Medium · 6.5 EPSS 2.3%

Mikrotik RouterOS Improper Enforcement of Behavioral Workflow Vulnerability

MikroTik · RouterOS

Summary

MikroTik RouterOS has a flaw in its SSH service: after a client-requested rekey, the server enters the connection protocol without ever requiring user authentication, which is an improper enforcement of behavioral workflow. An unauthenticated remote client can exploit this over the network, with no user interaction or prior credentials needed, to open a session channel and send an exec request, letting it create, overwrite, and reconstruct files in RouterOS's managed file namespace, including support files holding configuration and diagnostic data, on affected builds.

Official description · NVD

RouterOS SSH enters the connection protocol after a client-requested rekey even though user authentication was never attempted, allowing an unauthenticated client to open a session channel and send an exec request. On affected builds the server dispatches the command, enabling unauthenticated creation, overwrite, and reconstruction of files in the RouterOS managed file namespace, including support files containing configuration and diagnostic data.This issue was fixed in versions: 6.49.21 (Long-term), 7.23.4 (Long-term) and 7.24.2 (Stable)

Breakdown
74.2 / 100
Exploited
Yes, in CISA KEV
Reports
0
Tactics
3/15

How an attack unfolds

Based on mappings. Select a step to see the evidence.
  1. How attackers get in

  2. What they do

First seen exploited the day it was disclosed. Public exploit code (PoC-in-GitHub) appeared 21 days after disclosure.

  1. DisclosedFirst seen exploitedVulnCheck KEV evidenceday 0
  2. Added to CISA KEVEU database agrees+20 days
  3. Public exploit codePoC-in-GitHub+21 days

CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.

techniques

3 , grouped by in kill-chain order, 3 cited passages 3

Initial AccessTA0001

Exploit Public-Facing Application T1190 Medium
AI mapping from the description · how it is exploited

unauthenticated remote SSH exploitation of public-facing service

allowing an unauthenticated client to open a session channel and send an exec request
From the official description (NVD) Original (opens in a new tab) ↗

ExecutionTA0002

Command and Scripting Interpreter T1059 Medium
AI mapping from the description · primary impact

server dispatches attacker-supplied exec request commands

the server dispatches the command, enabling unauthenticated creation, overwrite
From the official description (NVD) Original (opens in a new tab) ↗

ImpactTA0040

Stored Data Manipulation T1565.001 Medium
AI mapping from the description · primary impact

overwrite and reconstruction of stored files

enabling unauthenticated creation, overwrite, and reconstruction of files
From the official description (NVD) Original (opens in a new tab) ↗

Detection

0 rules for this CVE · 250 general rules for its techniques

Rules for this CVE

0 that reference CVE-2026-67279 directly.

CVE-specific rules are not available in this build. Search SigmaHQ ↗

Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.

What security researchers reported

Not named in any threat report yet

Also mentioned in 29 community threat pulses (AlienVault OTX)

Weaker evidence

Pulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.

References

9 links, grouped by NVD tag
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