CVE-2026-67277（mikrotik routeros）の深刻度・悪用状況・対象バージョン
8.2 重要（CVSS 3.x） 悪用確認済み（CISA KEV） EPSS 取得中…
概要
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)
実際の攻撃で悪用されています。 CISA KEV への追加日: 2026-09-10。対象製品を使っている場合は最優先で対策してください。
CISA の要求対応: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CISA の要求対応: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
影響を受ける製品
| ベンダー | 製品 | 対象バージョン |
|---|---|---|
| mikrotik | routeros | ≥ 6.0 かつ < 6.49.21 |
| mikrotik | routeros | ≥ 7.0 かつ < 7.23.4 |
| mikrotik | routeros | ≥ 7.24 かつ < 7.24.2 |
基本情報
- 公開日
- 2026-09-05
- 最終更新
- 2026-09-11
- NVD の状態
- Analyzed
- 弱点の種類
- CWE-306
- CVSS 4.0
- 8.8（CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X）
対策の進め方
- 上の表で、使っている製品とバージョンが対象か確認します。
- ベンダーの公式アドバイザリ（下の参考情報の「Vendor Advisory」「Patch」）で修正版・回避策を確認します。
- 悪用が確認されているため、パッチ適用までの間もアクセス制限・侵害の痕跡確認を検討します。
- 日本語の情報は JVN iPedia で CVE-2026-67277 を検索 できます。
参考情報
- https://cert.pl/en/posts/2026/09/mikrotik-routeros-cve Third Party Advisory
- https://cert.pl/en/posts/2026/09/vulnerabilities-in-mikrotik-routeros-actively-exploited/ MitigationThird Party Advisory
- https://forum.mikrotik.com/t/6-49-21-long-term-is-released/272802 Release Notes
- https://forum.mikrotik.com/t/7-23-4-long-term-is-released/272801 Release Notes
- https://forum.mikrotik.com/t/7-24-2-stable-is-released/272800 Release Notes
- https://mikrotik.com/supportsec/september-2026-vulnerability/ Vendor Advisory
- https://npratley.net/reversing-mikrotiks-silent-patch-the-routeros-7-23-4-fix-they-wouldnt-explain/ ExploitThird Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-67277 US Government Resource
- NVD: CVE-2026-67277
- CVE.org: CVE-2026-67277
データ出典: NIST NVD、CISA KEV、FIRST EPSS。翻訳は参考情報で、正確性は原文を優先してください。