# Firefox Developer Edition (en-US) 138.0

Firefox Developer Edition (en-US) 138.0, released April 18, 2025, fixes 12 CVEs in Firefox Developer Edition (en-US). None of them is reported as exploited. Patch Radar priority: High. 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-138.0
- Platform: Windows apps
- Released: Apr 18, 2025
- Priority: High (Closes CVE-2025-2817, high severity)
- CVEs: 12, 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- Superseded by: [Firefox Developer Edition (en-US) 156.0](https://patchblox.com/security/data/product/windows-app/firefox-developer-edition-en-us.md), the latest version,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) |  | 138.0 |

## CVEs this fix closes

| CVE | Priority | Title | CVSS | EPSS | Exploitation |
|---|---|---|---:|---:|---|
| [CVE-2025-2817](https://patchblox.com/security/data/cve/CVE-2025-2817.md) | High | Privilege escalation in Thunderbird Updater | 8.8 | 0.0067 |  |
| [CVE-2025-4091](https://patchblox.com/security/data/cve/CVE-2025-4091.md) | High | Memory safety bugs fixed in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10 | 8.8 | 0.0051 |  |
| [CVE-2025-4083](https://patchblox.com/security/data/cve/CVE-2025-4083.md) | High | Process isolation bypass using "javascript:" URI links in cross-origin frames | 9.1 | 0.0046 |  |
| [CVE-2025-4087](https://patchblox.com/security/data/cve/CVE-2025-4087.md) | High | Unsafe attribute access during XPath parsing | 8.8 | 0.0032 |  |
| [CVE-2025-4085](https://patchblox.com/security/data/cve/CVE-2025-4085.md) | High | Potential information leakage and privilege escalation in UITour actor | 7.1 | 0.0031 |  |
| [CVE-2025-4082](https://patchblox.com/security/data/cve/CVE-2025-4082.md) | Routine | WebGL shader attribute memory corruption in Thunderbird for macOS | 5.9 | 0.0046 |  |
| [CVE-2025-4090](https://patchblox.com/security/data/cve/CVE-2025-4090.md) | Routine | Leaked library paths in Thunderbird for Android | 5.3 | 0.0033 |  |
| [CVE-2025-3608](https://patchblox.com/security/data/cve/CVE-2025-3608.md) | Routine | Race condition in nsHttpTransaction could lead to memory corruption | 6.5 | 0.0032 |  |
| [CVE-2025-4092](https://patchblox.com/security/data/cve/CVE-2025-4092.md) | Routine | Memory safety bugs fixed in Firefox 138 and Thunderbird 138 | 6.5 | 0.0031 |  |
| [CVE-2025-4086](https://patchblox.com/security/data/cve/CVE-2025-4086.md) | Routine | Specially crafted filename could be used to obscure download type | 6.5 | 0.0030 |  |
| [CVE-2025-4089](https://patchblox.com/security/data/cve/CVE-2025-4089.md) | Routine | Potential local code execution in "copy as cURL" command | 5.1 | 0.0019 |  |
| [CVE-2025-4088](https://patchblox.com/security/data/cve/CVE-2025-4088.md) | Routine | Cross-site request forgery via storage access API redirects | 6.5 | 0.0018 |  |

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Data as of 2026-11-08T06:59:42Z 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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