# KB4598243: January 2021 cumulative update for Windows 10 1607 KB4598243, released January 12, 2021, fixes 55 CVEs across 7 products. None of them is reported as exploited. Patch Radar priority: Urgent. - Web page: https://patchblox.com/security/fix/microsoft/kb4598243 - Platform: Microsoft - Released: Jan 12, 2021 - Priority: Urgent (Closes CVE-2021-1665, rated Critical) - CVEs: 55, exploited: 0, on CISA KEV: 0 - Vendor advisory: https://support.microsoft.com/help/4598243 ## Applies to | Product | Release | Fixed in | |---|---|---| | [Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1607 for 32-bit Systems](https://patchblox.com/security/data/product/microsoft/microsoft-edge-edgehtml-based-on-windows-10-version-1607-for-32-bit-systems.md) | | 14393.4169 | | [Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1607 for x64-based Systems](https://patchblox.com/security/data/product/microsoft/microsoft-edge-edgehtml-based-on-windows-10-version-1607-for-x64-based-systems.md) | | 14393.4169 | | [Microsoft Edge (EdgeHTML-based) on Windows Server 2016](https://patchblox.com/security/data/product/microsoft/microsoft-edge-edgehtml-based-on-windows-server-2016.md) | | 14393.4169 | | [Windows 10 Version 1607 for 32-bit Systems](https://patchblox.com/security/data/product/microsoft/windows-10-version-1607-for-32-bit-systems.md) | | 14393.4169 | | [Windows 10 Version 1607 for x64-based Systems](https://patchblox.com/security/data/product/microsoft/windows-10-version-1607-for-x64-based-systems.md) | | 14393.4169 | | [Windows Server 2016](https://patchblox.com/security/data/product/microsoft/windows-server-2016.md) | | 14393.4169 | | [Windows Server 2016 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/windows-server-2016-server-core-installation.md) | | 14393.4169 | ## CVEs this fix closes | CVE | Priority | Component | CVSS | EPSS | Exploitation | |---|---|---|---:|---:|---| | [CVE-2021-1665](https://patchblox.com/security/data/cve/CVE-2021-1665.md) | Urgent | Microsoft Graphics Component | 7.8 | 0.0406 | | | [CVE-2021-1668](https://patchblox.com/security/data/cve/CVE-2021-1668.md) | Urgent | Microsoft DTV-DVD Video Decoder | 7.8 | 0.0392 | | | [CVE-2021-1667](https://patchblox.com/security/data/cve/CVE-2021-1667.md) | Urgent | Windows Remote Procedure Call Runtime | 8.8 | 0.0387 | | | [CVE-2021-1658](https://patchblox.com/security/data/cve/CVE-2021-1658.md) | Urgent | Windows Remote Procedure Call Runtime | 8.8 | 0.0320 | | | [CVE-2021-1660](https://patchblox.com/security/data/cve/CVE-2021-1660.md) | Urgent | Windows Remote Procedure Call Runtime | 8.8 | 0.0320 | | | [CVE-2021-1666](https://patchblox.com/security/data/cve/CVE-2021-1666.md) | Urgent | Windows Remote Procedure Call Runtime | 8.8 | 0.0320 | | | [CVE-2021-1673](https://patchblox.com/security/data/cve/CVE-2021-1673.md) | Urgent | Windows Remote Procedure Call Runtime | 8.8 | 0.0320 | | | [CVE-2021-1705](https://patchblox.com/security/data/cve/CVE-2021-1705.md) | Urgent | Microsoft Edge (HTML-based) | 4.2 | 0.0207 | | | [CVE-2021-1709](https://patchblox.com/security/data/cve/CVE-2021-1709.md) | Urgent | Microsoft Graphics Component | 7.0 | 0.0079 | More likely | | [CVE-2021-1692](https://patchblox.com/security/data/cve/CVE-2021-1692.md) | High | Windows Hyper-V | 7.7 | 0.0424 | | | [CVE-2021-1700](https://patchblox.com/security/data/cve/CVE-2021-1700.md) | High | Windows Remote Procedure Call Runtime | 8.8 | 0.0387 | | | [CVE-2021-1701](https://patchblox.com/security/data/cve/CVE-2021-1701.md) | High | Windows Remote Procedure Call Runtime | 8.8 | 0.0387 | | | [CVE-2021-1694](https://patchblox.com/security/data/cve/CVE-2021-1694.md) | High | Windows Update Stack | 7.5 | 0.0351 | | | [CVE-2021-1710](https://patchblox.com/security/data/cve/CVE-2021-1710.md) | High | Windows Media | 7.8 | 0.0322 | | | [CVE-2021-1664](https://patchblox.com/security/data/cve/CVE-2021-1664.md) | High | Windows Remote Procedure Call Runtime | 8.8 | 0.0320 | | | [CVE-2021-1669](https://patchblox.com/security/data/cve/CVE-2021-1669.md) | High | Windows Remote Desktop | 8.8 | 0.0320 | | | [CVE-2021-1671](https://patchblox.com/security/data/cve/CVE-2021-1671.md) | High | Windows Remote Procedure Call Runtime | 8.8 | 0.0320 | | | [CVE-2021-1674](https://patchblox.com/security/data/cve/CVE-2021-1674.md) | High | Windows Remote Desktop | 8.8 | 0.0320 | | | [CVE-2021-1706](https://patchblox.com/security/data/cve/CVE-2021-1706.md) | High | Microsoft Windows | 7.3 | 0.0225 | | | [CVE-2021-1648](https://patchblox.com/security/data/cve/CVE-2021-1648.md) | High | Windows splwow64 | 7.8 | 0.0125 | Disclosed | | [CVE-2018-8455](https://patchblox.com/security/data/cve/CVE-2018-8455.md) | High | Windows Kernel | 7.0 | 0.0109 | | | [CVE-2021-1704](https://patchblox.com/security/data/cve/CVE-2021-1704.md) | High | Windows Hyper-V | 7.3 | 0.0103 | | | [CVE-2021-1657](https://patchblox.com/security/data/cve/CVE-2021-1657.md) | High | Microsoft Windows | 7.8 | 0.0095 | | | [CVE-2021-1685](https://patchblox.com/security/data/cve/CVE-2021-1685.md) | High | Windows AppX Deployment Extensions | 7.3 | 0.0094 | | | [CVE-2021-1695](https://patchblox.com/security/data/cve/CVE-2021-1695.md) | High | Windows Print Spooler Components | 7.8 | 0.0087 | | | [CVE-2021-1661](https://patchblox.com/security/data/cve/CVE-2021-1661.md) | High | Windows Installer | 7.8 | 0.0083 | | | [CVE-2021-1651](https://patchblox.com/security/data/cve/CVE-2021-1651.md) | High | Windows Diagnostic Hub | 7.8 | 0.0082 | | | [CVE-2021-1697](https://patchblox.com/security/data/cve/CVE-2021-1697.md) | High | Windows Installer | 7.8 | 0.0082 | | | [CVE-2021-1650](https://patchblox.com/security/data/cve/CVE-2021-1650.md) | High | Microsoft Windows | 7.8 | 0.0081 | | | [CVE-2021-1649](https://patchblox.com/security/data/cve/CVE-2021-1649.md) | High | Microsoft Windows | 7.8 | 0.0079 | | | [CVE-2021-1652](https://patchblox.com/security/data/cve/CVE-2021-1652.md) | High | Windows CSC Service | 7.8 | 0.0079 | | | [CVE-2021-1653](https://patchblox.com/security/data/cve/CVE-2021-1653.md) | High | Windows CSC Service | 7.8 | 0.0079 | | | [CVE-2021-1654](https://patchblox.com/security/data/cve/CVE-2021-1654.md) | High | Windows CSC Service | 7.8 | 0.0079 | | | [CVE-2021-1655](https://patchblox.com/security/data/cve/CVE-2021-1655.md) | High | Windows CSC Service | 7.8 | 0.0079 | | | [CVE-2021-1693](https://patchblox.com/security/data/cve/CVE-2021-1693.md) | High | Windows CSC Service | 7.8 | 0.0079 | | | [CVE-2021-1702](https://patchblox.com/security/data/cve/CVE-2021-1702.md) | High | Windows Remote Procedure Call | 7.8 | 0.0079 | | | [CVE-2021-1642](https://patchblox.com/security/data/cve/CVE-2021-1642.md) | High | Windows AppX Deployment Extensions | 7.8 | 0.0075 | | | [CVE-2021-1680](https://patchblox.com/security/data/cve/CVE-2021-1680.md) | High | Windows Diagnostic Hub | 7.8 | 0.0073 | | | [CVE-2021-1659](https://patchblox.com/security/data/cve/CVE-2021-1659.md) | High | Windows CSC Service | 7.8 | 0.0070 | | | [CVE-2021-1681](https://patchblox.com/security/data/cve/CVE-2021-1681.md) | High | Windows WalletService | 7.8 | 0.0070 | | | [CVE-2021-1686](https://patchblox.com/security/data/cve/CVE-2021-1686.md) | High | Windows WalletService | 7.8 | 0.0070 | | | [CVE-2021-1687](https://patchblox.com/security/data/cve/CVE-2021-1687.md) | High | Windows WalletService | 7.8 | 0.0070 | | | [CVE-2021-1688](https://patchblox.com/security/data/cve/CVE-2021-1688.md) | High | Windows CSC Service | 7.8 | 0.0070 | | | [CVE-2021-1689](https://patchblox.com/security/data/cve/CVE-2021-1689.md) | High | Microsoft Windows | 7.8 | 0.0070 | | | [CVE-2021-1690](https://patchblox.com/security/data/cve/CVE-2021-1690.md) | High | Windows WalletService | 7.8 | 0.0070 | | | [CVE-2021-1645](https://patchblox.com/security/data/cve/CVE-2021-1645.md) | Routine | Windows DP API | 5.0 | 0.0785 | | | [CVE-2021-1696](https://patchblox.com/security/data/cve/CVE-2021-1696.md) | Routine | Microsoft Graphics Component | 5.5 | 0.0470 | | | [CVE-2021-1679](https://patchblox.com/security/data/cve/CVE-2021-1679.md) | Routine | Windows CryptoAPI | 6.5 | 0.0374 | | | [CVE-2021-1708](https://patchblox.com/security/data/cve/CVE-2021-1708.md) | Routine | Microsoft Graphics Component | 5.7 | 0.0372 | | | [CVE-2021-1656](https://patchblox.com/security/data/cve/CVE-2021-1656.md) | Routine | Windows TPM Device Driver | 5.5 | 0.0301 | | | [CVE-2021-1699](https://patchblox.com/security/data/cve/CVE-2021-1699.md) | Routine | Microsoft Windows | 5.5 | 0.0214 | | | [CVE-2021-1683](https://patchblox.com/security/data/cve/CVE-2021-1683.md) | Routine | Microsoft Bluetooth Driver | 5.0 | 0.0168 | | | [CVE-2021-1684](https://patchblox.com/security/data/cve/CVE-2021-1684.md) | Routine | Microsoft Bluetooth Driver | 5.0 | 0.0163 | | | [CVE-2021-1676](https://patchblox.com/security/data/cve/CVE-2021-1676.md) | Routine | Microsoft Windows | 5.5 | 0.0132 | | | [CVE-2021-1637](https://patchblox.com/security/data/cve/CVE-2021-1637.md) | Routine | Microsoft Windows DNS | 5.5 | 0.0122 | | --- Data as of 2026-11-07T18:46:35Z UTC. 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