# Firefox Developer Edition (en-US) 142.0

Firefox Developer Edition (en-US) 142.0, released August 8, 2025, fixes 9 CVEs in Firefox Developer Edition (en-US). None of them is reported as exploited. Patch Radar priority: Urgent. The latest Firefox Developer Edition (en-US) is 156.0, which also fixes every one of these CVEs.

- Web page: https://patchblox.com/security/fix/windows-app/mozilla.firefox.developeredition-142.0
- Platform: Windows apps
- Released: Aug 8, 2025
- Priority: Urgent (Closes CVE-2025-9187, rated Critical)
- CVEs: 9, exploited: 0, on CISA KEV: 0
- Superseded by: [Firefox Developer Edition (en-US) 156.0](https://patchblox.com/security/data/product/windows-app/firefox-developer-edition-en-us.md), the latest version, which also fixes every CVE listed here

## Applies to

| Product | Release | Fixed in |
|---|---|---|
| [Firefox Developer Edition (en-US)](https://patchblox.com/security/data/product/windows-app/firefox-developer-edition-en-us.md) |  | 142.0 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2025-9187](https://patchblox.com/security/data/cve/CVE-2025-9187.md) | Urgent | Memory safety bugs fixed in Firefox 142 and Thunderbird 142 | 9.8 | 0.0049 |  |
| [CVE-2025-9179](https://patchblox.com/security/data/cve/CVE-2025-9179.md) | High | Sandbox escape due to invalid pointer in the Audio/Video: GMP component | 9.8 | 0.0061 |  |
| [CVE-2025-9185](https://patchblox.com/security/data/cve/CVE-2025-9185.md) | High | Memory safety bugs fixed in Firefox ESR 115.27, Firefox ESR 128.14, Thunderbird ESR 128.14, Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142 | 8.1 | 0.0051 |  |
| [CVE-2025-9182](https://patchblox.com/security/data/cve/CVE-2025-9182.md) | High | Denial-of-service due to out-of-memory in the Graphics: WebRender component | 7.5 | 0.0041 |  |
| [CVE-2025-9184](https://patchblox.com/security/data/cve/CVE-2025-9184.md) | High | Memory safety bugs fixed in Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142 | 8.1 | 0.0040 |  |
| [CVE-2025-9181](https://patchblox.com/security/data/cve/CVE-2025-9181.md) | High | Uninitialized memory in the JavaScript Engine component | 7.5 | 0.0039 |  |
| [CVE-2025-9180](https://patchblox.com/security/data/cve/CVE-2025-9180.md) | High | Same-origin policy bypass in the Graphics: Canvas2D component | 8.1 | 0.0027 |  |
| [CVE-2025-9183](https://patchblox.com/security/data/cve/CVE-2025-9183.md) | Routine | Spoofing issue in the Address Bar component | 6.5 | 0.0027 |  |
| [CVE-2025-9186](https://patchblox.com/security/data/cve/CVE-2025-9186.md) | Routine | Spoofing issue in the Address Bar component of Firefox Focus for Android | 6.5 | 0.0022 |  |

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Data as of 2026-11-08T13:06:02Z 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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