# KB5052042: February 2025 security update

KB5052042, released February 11, 2025, fixes 23 CVEs across 2 products. One of them is being exploited (CVE-2025-21418); 1 on CISA KEV. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/fix/microsoft/kb5052042
- Platform: Microsoft
- Released: Feb 11, 2025
- Priority: Patch now (Closes CVE-2025-21418, exploited (CISA KEV))
- CVEs: 23, exploited: 1, on CISA KEV: 1
- Vendor advisory: https://support.microsoft.com/help/5052042

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Windows Server 2012 R2](https://patchblox.com/security/data/product/microsoft/windows-server-2012-r2.md) |  |  |
| [Windows Server 2012 R2 (Server Core installation)](https://patchblox.com/security/data/product/microsoft/windows-server-2012-r2-server-core-installation.md) |  |  |

## CVEs this fix closes

| CVE | Priority | Component | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2025-21418](https://patchblox.com/security/data/cve/CVE-2025-21418.md) | Patch now | Windows Ancillary Function Driver for WinSock | 7.8 | 0.0213 | CISA KEV |
| [CVE-2025-21377](https://patchblox.com/security/data/cve/CVE-2025-21377.md) | Urgent | Windows NTLM | 6.5 | 0.3993 | Disclosed |
| [CVE-2025-21376](https://patchblox.com/security/data/cve/CVE-2025-21376.md) | Urgent | Windows LDAP - Lightweight Directory Access Protocol | 8.1 | 0.0931 | More likely |
| [CVE-2025-21420](https://patchblox.com/security/data/cve/CVE-2025-21420.md) | Urgent | Windows Disk Cleanup Tool | 7.8 | 0.0367 | More likely |
| [CVE-2025-21419](https://patchblox.com/security/data/cve/CVE-2025-21419.md) | Urgent | Windows Setup Files Cleanup | 7.1 | 0.0072 | More likely |
| [CVE-2025-21181](https://patchblox.com/security/data/cve/CVE-2025-21181.md) | High | Windows Message Queuing | 7.5 | 0.0348 |  |
| [CVE-2025-21371](https://patchblox.com/security/data/cve/CVE-2025-21371.md) | High | Windows Telephony Service | 8.8 | 0.0243 |  |
| [CVE-2025-21368](https://patchblox.com/security/data/cve/CVE-2025-21368.md) | High | Microsoft Digest Authentication | 8.8 | 0.0215 |  |
| [CVE-2025-21369](https://patchblox.com/security/data/cve/CVE-2025-21369.md) | High | Microsoft Digest Authentication | 8.8 | 0.0215 |  |
| [CVE-2025-21406](https://patchblox.com/security/data/cve/CVE-2025-21406.md) | High | Windows Telephony Service | 8.8 | 0.0182 |  |
| [CVE-2025-21407](https://patchblox.com/security/data/cve/CVE-2025-21407.md) | High | Windows Telephony Service | 8.8 | 0.0182 |  |
| [CVE-2025-21410](https://patchblox.com/security/data/cve/CVE-2025-21410.md) | High | Windows Routing and Remote Access Service (RRAS) | 8.8 | 0.0182 |  |
| [CVE-2025-21190](https://patchblox.com/security/data/cve/CVE-2025-21190.md) | High | Windows Telephony Service | 8.8 | 0.0181 |  |
| [CVE-2025-21200](https://patchblox.com/security/data/cve/CVE-2025-21200.md) | High | Windows Telephony Service | 8.8 | 0.0181 |  |
| [CVE-2025-21201](https://patchblox.com/security/data/cve/CVE-2025-21201.md) | High | Windows Telephony Server | 8.8 | 0.0181 |  |
| [CVE-2025-21208](https://patchblox.com/security/data/cve/CVE-2025-21208.md) | High | Windows Routing and Remote Access Service (RRAS) | 8.8 | 0.0181 |  |
| [CVE-2025-21373](https://patchblox.com/security/data/cve/CVE-2025-21373.md) | High | Windows Installer | 7.8 | 0.0080 |  |
| [CVE-2025-21375](https://patchblox.com/security/data/cve/CVE-2025-21375.md) | High | Microsoft Streaming Service | 7.8 | 0.0065 |  |
| [CVE-2025-21359](https://patchblox.com/security/data/cve/CVE-2025-21359.md) | High | Windows Kernel | 7.8 | 0.0056 |  |
| [CVE-2025-21350](https://patchblox.com/security/data/cve/CVE-2025-21350.md) | Routine | Windows Kerberos | 5.9 | 0.0213 |  |
| [CVE-2025-21352](https://patchblox.com/security/data/cve/CVE-2025-21352.md) | Routine | Windows Internet Connection Sharing (ICS) | 6.5 | 0.0104 |  |
| [CVE-2025-21347](https://patchblox.com/security/data/cve/CVE-2025-21347.md) | Routine | Windows Update Stack | 6.0 | 0.0066 |  |
| [CVE-2025-21337](https://patchblox.com/security/data/cve/CVE-2025-21337.md) | Routine | Microsoft Windows | 3.3 | 0.0061 |  |

---

Data as of 2026-11-07T06:34:28Z 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