# CVE-2020-12391: Firefox ESR: Documents formed using data: URLs in an OBJECT element failed to inherit the CSP of the creating context.

CVE-2020-12391 is fixed in 4 products on 2 platforms, first by firefox 76.0+build2-0ubuntu0.18.04.1, released May 6, 2020. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2020-12391
- Priority: High
- CVSS: 7.5 (Medium)
- EPSS: 0.0146
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 6, 2020
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2020-12391

## Description

Documents formed using data: URLs in an OBJECT element failed to inherit the CSP of the creating context. This allowed the execution of scripts that should have been blocked, albeit with a unique opaque origin. This vulnerability affects Firefox < 76.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Mozilla Firefox ESR (en-US) | 78.0esr | [Mozilla Firefox ESR (en-US) 78.0esr](https://patchblox.com/security/data/fix/windows-app/mozilla.firefox.esr-78.0esr.md) | Jun 25, 2020 |
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 76.0+build2-0ubuntu0.18.04.1 | [firefox 76.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-76.0-build2-0ubuntu0.18.04.1.md) | May 6, 2020 |
| Linux | firefox Ubuntu 20.04 LTS (focal) | 76.0+build2-0ubuntu0.20.04.1 | [firefox 76.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-76.0-build2-0ubuntu0.20.04.1.md) | May 6, 2020 |
| Linux | firefox-geckodriver Ubuntu 18.04.6 LTS (bionic) | 76.0+build2-0ubuntu0.18.04.1 | [firefox-geckodriver 76.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-geckodriver-76.0-build2-0ubuntu0.18.04.1.md) | May 6, 2020 |
| Linux | firefox-geckodriver Ubuntu 20.04 LTS (focal) | 76.0+build2-0ubuntu0.20.04.1 | [firefox-geckodriver 76.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-geckodriver-76.0-build2-0ubuntu0.20.04.1.md) | May 6, 2020 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 76.0+build2-0ubuntu0.18.04.1 | [firefox-mozsymbols 76.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-76.0-build2-0ubuntu0.18.04.1.md) | May 6, 2020 |
| Linux | firefox-mozsymbols Ubuntu 20.04 LTS (focal) | 76.0+build2-0ubuntu0.20.04.1 | [firefox-mozsymbols 76.0+build2-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-mozsymbols-76.0-build2-0ubuntu0.20.04.1.md) | May 6, 2020 |

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