# CVE-2021-1663: Windows Projected File System FS Filter Driver Information Disclosure Vulnerability

CVE-2021-1663 is fixed in 7 products on 1 platform, first by KB4598242, released January 12, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-1663
- Priority: Routine
- CVSS: 5.5 (Important)
- EPSS: 0.0122
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Vendor exploitability assessment: Exploitation Less Likely
- Published: Jan 12, 2021
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-1663

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Microsoft | Windows 10 Version 2004 for 32-bit Systems |  | [KB4598242](https://patchblox.com/security/data/fix/microsoft/kb4598242.md) | Jan 12, 2021 |
| Microsoft | Windows 10 Version 2004 for ARM64-based Systems |  | [KB4598242](https://patchblox.com/security/data/fix/microsoft/kb4598242.md) | Jan 12, 2021 |
| Microsoft | Windows 10 Version 2004 for x64-based Systems |  | [KB4598242](https://patchblox.com/security/data/fix/microsoft/kb4598242.md) | Jan 12, 2021 |
| Microsoft | Windows 10 Version 20H2 for 32-bit Systems |  | [KB4598242](https://patchblox.com/security/data/fix/microsoft/kb4598242.md) | Jan 12, 2021 |
| Microsoft | Windows 10 Version 20H2 for ARM64-based Systems |  | [KB4598242](https://patchblox.com/security/data/fix/microsoft/kb4598242.md) | Jan 12, 2021 |
| Microsoft | Windows Server, version 2004 (Server Core installation) |  | [KB4598242](https://patchblox.com/security/data/fix/microsoft/kb4598242.md) | Jan 12, 2021 |
| Microsoft | Windows Server, version 20H2 (Server Core Installation) |  | [KB4598242](https://patchblox.com/security/data/fix/microsoft/kb4598242.md) | Jan 12, 2021 |

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Data as of 2026-11-07T12:40:37Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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