# CVE-2023-34415: Mozilla Firefox and 2 others: When choosing a site-isolated process for a document loaded from a data: URL that was the result of a…

CVE-2023-34415 is fixed in 5 products on 2 platforms, first by firefox 114.0+build3-0ubuntu0.20.04.1, released June 6, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2023-34415
- Priority: Routine
- CVSS: 6.1 (Medium)
- EPSS: 0.0041
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 6, 2023
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2023-34415

## Description

When choosing a site-isolated process for a document loaded from a data: URL that was the result of a redirect, Firefox would load that document in the same process as the site that issued the redirect. This bypassed the site-isolation protections against Spectre-like attacks on sites that host an "open redirect". Firefox no longer follows HTTP redirects to data: URLs. This vulnerability affects Firefox < 114.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Mozilla Firefox (en-US) | 114.0.1 | [Mozilla Firefox (en-US) 114.0.1](https://patchblox.com/security/data/fix/windows-app/mozilla.firefox-114.0.1.md) | Jun 12, 2023 |
| Windows apps | Mozilla Firefox ESR (en-US) | 115.4.0 | [Mozilla Firefox ESR (en-US) 115.4.0](https://patchblox.com/security/data/fix/windows-app/mozilla.firefox.esr-115.4.0.md) | Oct 17, 2023 |
| Linux | firefox Ubuntu 20.04 LTS (focal) | 114.0+build3-0ubuntu0.20.04.1 | [firefox 114.0+build3-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-114.0-build3-0ubuntu0.20.04.1.md) | Jun 6, 2023 |
| Linux | firefox-geckodriver Ubuntu 20.04 LTS (focal) | 114.0+build3-0ubuntu0.20.04.1 | [firefox-geckodriver 114.0+build3-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-geckodriver-114.0-build3-0ubuntu0.20.04.1.md) | Jun 6, 2023 |
| Linux | firefox-mozsymbols Ubuntu 20.04 LTS (focal) | 114.0+build3-0ubuntu0.20.04.1 | [firefox-mozsymbols 114.0+build3-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-mozsymbols-114.0-build3-0ubuntu0.20.04.1.md) | Jun 6, 2023 |

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Data as of 2026-11-09T07:25:28Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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