CVE-2026-67277Network attack vector

Kernel memory disclosure and restart via unauthenticated btest

Published Sep 5, 2026 · Updated Sep 9, 2026

Missing authentication in MikroTik RouterOS btest allows remote attackers to disclose kernel memory or restart the device over the network. The service accepts a related connection before its primary session authenticates, then either sends an uninitialized kernel-buffer tail or underflows an inverted packet-size interval. The bandwidth-test server must be network reachable; successful requests disclose kernel data in UDP traffic or restart the RouterOS kernel.

CVSS severity8.8
High
EPSS probability0.87%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authentication in MikroTik RouterOS btest allows remote attackers to disclose kernel memory or restart the device over the network. The service accepts a related connection before its primary session authenticates, then either sends an uninitialized kernel-buffer tail or underflows an inverted packet-size interval. The bandwidth-test server must be network reachable; successful requests disclose kernel data in UDP traffic or restart the RouterOS kernel.

The record

CVE
CVE-2026-67277
Published
Sep 5, 2026
Updated
Sep 9, 2026
Vendor
MikroTik
Product
RouterOS
Classifications
CWE-306, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 5, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.0.0 <6.49.21
  2. Affected versionversion=7.0.0 <7.23.4
  3. Affected versionversion=7.24 <7.24.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

MikroTik · RouterOSversion=6.0.0 <6.49.21; version=7.0.0 <7.23.4; version=7.24 <7.24.2

Published CVSS scores

8.8CERT PolskaCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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