2026年9月12日の
セキュリティ情報

Subject: [Urgent] Please Update Your Browser and Windows OS

Hi everyone,
We have received reports of attacks exploiting vulnerabilities in Google Chrome and Windows. If left unpatched, these could allow malicious software to run on your device.

Action required:
1. Update Google Chrome to the latest version (via Settings > About Chrome).
2. Run Windows Update and install all available security patches.

Deadline: End of today

件名: 【共有】BlueMoon エクスプロイトキット (Chrome/Windows 脆弱性) 対応について

お疲れさまです。BlueMoonと呼ばれる新種のエクスプロイトキットに関する情報共有です。

■ 概要
ChromeのV8エンジンにおけるゼロデイ2件（CVE-2026-85046, CVE-2026-87491）と、Windowsの権限昇格脆弱性（CVE-2026-85880）をチェーンさせ、標的への侵入と権限昇格を行う攻撃が観測されています。中国系APT（Violet Typhoon等）による利用が確認されています。

■ 影響範囲
- Google Chrome (旧バージョン)
- Microsoft Windows (CVE-2026-85880 適用前バージョン)

■ 対応手順
1. 全端末のGoogle Chromeが最新版に更新されているか確認し、未適用の場合は強制更新を検討してください。
2. 2026年9月のWindows Patch Tuesday以降の更新プログラムが適用されているか確認してください。

■ 参考情報
- Proofpoint Threat Intelligence Report

対応優先度: 高
対応期限: 至急

Subject: [Technical Alert] BlueMoon Exploit Kit (Chrome/Windows Vulnerabilities)

Dear Security Team,

We are sharing information regarding a new exploit kit named 'BlueMoon' observed in the wild.

■ Overview
The kit chains two Chrome zero-days (CVE-2026-85046, CVE-2026-87491) affecting the V8 engine with a Windows privilege escalation vulnerability (CVE-2026-85880). This activity has been linked to China-aligned actors, including Violet Typhoon.

■ Scope
- Google Chrome (unpatched versions)
- Microsoft Windows (versions prior to the September 2026 patch)

■ Mitigation Steps
1. Ensure all corporate endpoints are running the latest version of Google Chrome.
2. Verify that the September 2026 Windows security updates have been successfully deployed across the environment.

■ Reference
- Proofpoint Threat Intelligence Report

Priority: High
Deadline: Immediate

Subject: [Urgent] Vulnerabilities in JFrog, ConnectWise, and MikroTik (Added to CISA KEV)

Dear Team,

This is a technical alert regarding the addition of several vulnerabilities to the CISA KEV catalog.

■ Overview
CISA has flagged vulnerabilities in JFrog Artifactory, ConnectWise ScreenConnect, and MikroTik RouterOS as being actively exploited. Key risks include privilege escalation (CVE-2026-42016), authentication bypass (CVE-2026-42018), and remote file execution (CVE-2026-84869).

■ Affected Products
- JFrog Artifactory
- ConnectWise ScreenConnect
- MikroTik RouterOS

■ Action Plan
1. Identify if these products are deployed within our infrastructure.
2. Apply the latest security updates provided by the respective vendors immediately.
3. Review authentication and access logs for signs of unauthorized activity.

■ Reference
- CISA Known Exploited Vulnerabilities (KEV) Catalog

Priority: High
Deadline: Immediate

Subject: [Security Alert] GitLab Path Traversal Vulnerability (CVE-2026-85706)

Dear IT/Security Team,

This is an alert regarding a critical vulnerability in GitLab.

■ Overview
A path traversal vulnerability (CVE-2026-85706) affecting GitLab Community Edition and Enterprise Edition has been added to CISA's Known Exploited Vulnerabilities (KEV) Catalog due to evidence of active exploitation.

■ Scope
- GitLab Community Edition
- GitLab Enterprise Edition

■ Remediation Steps
1. Identify all GitLab instances within the environment.
2. Apply the latest security patches provided by GitLab immediately.
3. Review system logs for any signs of compromise prior to patching.

■ Reference
- CISA KEV Catalog

Priority: High
Deadline: Immediate