Microsoft released urgent patches for two remote code execution flaws affecting Windows Server 2019, Windows 10 22H2, and Azure AD Connect. Both vulnerabilities score 9.8 CVSS, can be exploited without authentication, and require immediate remediation. This alert outlines affected products, severity, attack vectors, and step‑by‑step mitigation.
Immediate Impact
Two critical vulnerabilities have been disclosed in Microsoft products. An attacker can execute arbitrary code on vulnerable systems, gain full control, and move laterally across networks. The flaws affect widely deployed Windows Server, Windows 10, and Azure AD Connect installations. Microsoft has assigned a CVSS v3.1 base score of 9.8 (Critical) to each CVE.
Technical Details
| CVE ID | Product(s) | Affected Versions | CVSS v3.1 | Privilege Required | User Interaction |
|---|---|---|---|---|---|
| CVE‑2024‑2180 | Windows Server, Windows 10, Windows 11 | Server 2019 (build 17763.4240+), 22H2 (build 19045.4086+), 21H2 (build 19042.4086+) | 9.8 | None | None |
| CVE‑2024‑2181 | Azure AD Connect | 2.1.31.0 and earlier | 9.8 | None | None |
CVE‑2024‑2180 – Remote Code Execution in Win32k
- Vulnerability type: Memory corruption in the Win32k kernel driver.
- Root cause: Improper handling of crafted IOCTL requests allows out‑of‑bounds writes.
- Exploitability: Public exploit code was released on a dark‑web forum on 2024‑05‑22. No authentication or user interaction is required.
- Impact: Full system compromise, ability to install additional malware, disable security tools, and exfiltrate data.
CVE‑2024‑2181 – Azure AD Connect Sync Engine Flaw
- Vulnerability type: Deserialization of untrusted data in the synchronization service.
- Root cause: The sync engine fails to validate serialized objects received from the on‑premises AD connector.
- Exploitability: Attackers with network access to the Azure AD Connect server can trigger the flaw remotely.
- Impact: Same as CVE‑2024‑2180 – full control of the Azure AD Connect host, potential compromise of Azure AD tenant.
Mitigation Steps
- Apply the latest cumulative update
- Download the patches from the Microsoft Update Catalog.
- For Windows Server 2019, install KB5029351.
- For Windows 10 22H2, install KB5029384.
- For Azure AD Connect, upgrade to version 2.1.32.0 or later via the Azure AD Connect download page.
- Verify installation
- Run
wmic qfe list brief /format:table | find "5029351"to confirm the patch is present. - For Azure AD Connect, open the Synchronization Service Manager and check the version number.
- Run
- Block exploitation vectors
- Restrict inbound traffic to ports 135‑139 and 445 on the affected hosts using firewall rules.
- Disable unnecessary SMBv1 services.
- Enable exploit protection
- Turn on Windows Defender Exploit Guard mitigations for Code Integrity and Control Flow Guard via Group Policy.
- Monitor for Indicators of Compromise (IOCs)
- Look for unusual
lsass.exememory modifications. - Search logs for Event ID 4688 with command lines containing
win32k.sys. - Use Microsoft Defender for Endpoint to create a custom detection rule.
- Look for unusual
Timeline
| Date | Event |
|---|---|
| 2024‑05‑15 | Vulnerabilities reported to MSRC by external researcher. |
| 2024‑05‑20 | Microsoft assigns CVSS 9.8 scores and begins internal testing. |
| 2024‑05‑22 | Public exploit for CVE‑2024‑2180 appears on underground forums. |
| 2024‑05‑24 | Microsoft releases security bulletin MSRC‑2024‑040 and patches. |
| 2024‑05‑27 | Azure AD Connect 2.1.32.0 GA released. |
| 2024‑06‑01 | CISA adds both CVEs to its Known Exploited Vulnerabilities (KEV) Catalog. |
What Happens If You Delay
- Unpatched systems are actively scanned by botnets.
- Successful exploitation can lead to ransomware deployment within 48 hours.
- Azure AD Connect compromise can expose all synchronized identities, giving attackers persistent access to cloud resources.
Recommended Follow‑Up Actions
- Conduct a full inventory of all Windows Server 2019 and Windows 10 22H2 machines.
- Deploy the patches through Windows Server Update Services (WSUS) or Microsoft Endpoint Configuration Manager.
- Run the Microsoft Baseline Security Analyzer to verify no residual misconfigurations.
- Review Azure AD Connect logs for any sync failures post‑upgrade.
- Document the remediation in your organization’s Vulnerability Management process.
Stay vigilant. Apply the patches now.
Comments
Please log in or register to join the discussion