JPCERT-AT-2023-0005
                                                             JPCERT/CC
                                                            2023-03-15

                 <<< JPCERT/CC Alert 2023-03-15 >>>

           Microsoft Releases March 2023 Security Updates

       https://www.jpcert.or.jp/english/at/2023/at230005.html


I. Overview
Microsoft has released March 2023 Security Updates to address the
vulnerabilities in their products. Remote attackers leveraging
these vulnerabilities may be able to execute arbitrary code. It is
recommended to check the information provided by Microsoft and
apply the updates.

    Microsoft Corporation
    March 2023 Security Updates
    https://msrc.microsoft.com/update-guide/en-us/releaseNote/2023-Mar

According to Microsoft, among these vulnerabilities, the following
vulnerabilities have been confirmed to be exploited in the wild. Please
consider applying the security update programs by referring to the
information provided by Microsoft.

CVE-2023-23397 is a privilege escalation vulnerability in Microsoft
Outlook for Windows that is triggered when an attacker sends
a specially-crafted message that allows the user's NTLM negotiation
message to be sent to a threat actor-controlled server. No user
interaction is required. Online services such as Microsoft 365
are not affected. Microsoft is aware of limited, targeted abuse of a
vulnerability, and strongly recommends updating the product.

    CVE-2023-23397
    Microsoft Outlook Elevation of Privilege Vulnerability
    https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2023-23397

    Microsoft MSRC
    Microsoft Mitigates Outlook Elevation of Privilege Vulnerability
    https://msrc.microsoft.com/blog/2023/03/microsoft-mitigates-outlook-elevation-of-privilege-vulnerability/

CVE-2023-24880 is a vulnerability that bypasses the security feature
of Windows SmartScreen. Google TAG, which discovered and reported the
vulnerability, explained that the vulnerability was exploited in
activities to distribute files that lead to ransomware infections.

    CVE-2023-24880
    Windows SmartScreen Security Feature Bypass Vulnerability
    https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2023-24880

    Google Threat Analysis Group
    Magniber ransomware actors used a variant of Microsoft SmartScreen bypass
    https://blog.google/threat-analysis-group/magniber-ransomware-actors-used-a-variant-of-microsoft-smartscreen-bypass/


II. Solution
Please apply the security update programs through Microsoft Update,
Windows Update, etc. as soon as possible.

    Microsoft Update Catalog
    https://www.catalog.update.microsoft.com/

    Windows Update: FAQ
    https://support.microsoft.com/en-us/help/12373/windows-update-faq


III. References
    Microsoft Corporation
    Release Notes
    https://msrc.microsoft.com/update-guide/releaseNote

    Microsoft The Exchange Team
    Released: March 2023 Exchange Server Security Updates
    https://techcommunity.microsoft.com/t5/exchange-team-blog/released-march-2023-exchange-server-security-updates/ba-p/3764224


If you have any information regarding this alert, please contact
JPCERT/CC.

======================================================================
JPCERT Coordination Center (Early Warning Group)
MAIL: ew-info@jpcert.or.jp
https://www.jpcert.or.jp/english/