# Microsoft Edge Dev 140.0.3421.0

Microsoft Edge Dev 140.0.3421.0, released July 7, 2025, fixes 14 CVEs in Microsoft Edge Dev. None of them is reported as exploited. Patch Radar priority: Urgent. The latest Microsoft Edge Dev is 159.0.4393.0, which also fixes every one of these CVEs.

- Web page: https://patchblox.com/security/fix/windows-app/microsoft.edge.dev-140.0.3421.0
- Platform: Windows apps
- Released: Jul 7, 2025
- Priority: Urgent (Closes CVE-2025-9478, rated Critical)
- CVEs: 14, exploited: 0, on CISA KEV: 0
- Superseded by: [Microsoft Edge Dev 159.0.4393.0](https://patchblox.com/security/data/product/windows-app/microsoft-edge-dev.md), the latest version, which also fixes every CVE listed here

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Microsoft Edge Dev](https://patchblox.com/security/data/product/windows-app/microsoft-edge-dev.md) |  | 140.0.3421.0 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2025-9478](https://patchblox.com/security/data/cve/CVE-2025-9478.md) | Urgent | Chromium: CVE-2025-9478 Use after free in ANGLE | 9.6 | 0.0742 |  |
| [CVE-2025-8901](https://patchblox.com/security/data/cve/CVE-2025-8901.md) | Urgent | Chromium: CVE-2025-8901 Out of bounds write in ANGLE | 9.6 | 0.0034 |  |
| [CVE-2025-8578](https://patchblox.com/security/data/cve/CVE-2025-8578.md) | High | Chromium: CVE-2025-8578 Use after free in Cast | 8.8 | 0.0036 |  |
| [CVE-2025-8576](https://patchblox.com/security/data/cve/CVE-2025-8576.md) | High | Chromium: CVE-2025-8576 Use after free in Extensions | 8.8 | 0.0034 |  |
| [CVE-2025-8879](https://patchblox.com/security/data/cve/CVE-2025-8879.md) | High | Chromium: CVE-2025-8879 Heap buffer overflow in libaom | 8.8 | 0.0030 |  |
| [CVE-2025-8880](https://patchblox.com/security/data/cve/CVE-2025-8880.md) | High | Chromium: CVE-2025-8880 Race in V8 | 8.8 | 0.0028 |  |
| [CVE-2025-8882](https://patchblox.com/security/data/cve/CVE-2025-8882.md) | High | Chromium: CVE-2025-8882 Use after free in Aura | 8.8 | 0.0027 |  |
| [CVE-2025-8581](https://patchblox.com/security/data/cve/CVE-2025-8581.md) | Routine | Chromium: CVE-2025-8581 Inappropriate implementation in Extensions | 4.3 | 0.0030 |  |
| [CVE-2025-8577](https://patchblox.com/security/data/cve/CVE-2025-8577.md) | Routine | Chromium: CVE-2025-8577 Inappropriate implementation in Picture In Picture | 4.3 | 0.0026 |  |
| [CVE-2025-8579](https://patchblox.com/security/data/cve/CVE-2025-8579.md) | Routine | Chromium: CVE-2025-8579 Inappropriate implementation in Gemini Live in Chrome | 4.3 | 0.0026 |  |
| [CVE-2025-8580](https://patchblox.com/security/data/cve/CVE-2025-8580.md) | Routine | Chromium: CVE-2025-8580 Inappropriate implementation in Filesystems | 4.3 | 0.0026 |  |
| [CVE-2025-8582](https://patchblox.com/security/data/cve/CVE-2025-8582.md) | Routine | Chromium: CVE-2025-8582 Insufficient validation of untrusted input in DOM | 4.3 | 0.0026 |  |
| [CVE-2025-8881](https://patchblox.com/security/data/cve/CVE-2025-8881.md) | Routine | Chromium: CVE-2025-8881 Inappropriate implementation in File Picker | 6.5 | 0.0026 |  |
| [CVE-2025-8583](https://patchblox.com/security/data/cve/CVE-2025-8583.md) | Routine | Chromium: CVE-2025-8583 Inappropriate implementation in Permissions | 4.3 | 0.0024 |  |

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Data as of 2026-11-11T13:47:35Z 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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