# CVE-2020-12407: Firefox ESR: Mozilla Developer Nicolas Silva found that when using WebRender, Firefox would under certain conditions…

CVE-2020-12407 is fixed in 4 products on 2 platforms, first by firefox 77.0.1+build1-0ubuntu0.18.04.1, released June 2, 2020. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-12407
- Priority: Routine
- CVSS: 6.5 (Medium)
- EPSS: 0.0097
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 1, 2020
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2020-12407

## Description

Mozilla Developer Nicolas Silva found that when using WebRender, Firefox would under certain conditions leak arbitrary GPU memory to the visible screen. The leaked memory content was visible to the user, but not observable from web content. This vulnerability affects Firefox < 77.

## 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) | 77.0.1+build1-0ubuntu0.18.04.1 | [firefox 77.0.1+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-77.0.1-build1-0ubuntu0.18.04.1.md) | Jun 2, 2020 |
| Linux | firefox Ubuntu 20.04 LTS (focal) | 77.0.1+build1-0ubuntu0.20.04.1 | [firefox 77.0.1+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-77.0.1-build1-0ubuntu0.20.04.1.md) | Jun 2, 2020 |
| Linux | firefox-geckodriver Ubuntu 18.04.6 LTS (bionic) | 77.0.1+build1-0ubuntu0.18.04.1 | [firefox-geckodriver 77.0.1+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-geckodriver-77.0.1-build1-0ubuntu0.18.04.1.md) | Jun 2, 2020 |
| Linux | firefox-geckodriver Ubuntu 20.04 LTS (focal) | 77.0.1+build1-0ubuntu0.20.04.1 | [firefox-geckodriver 77.0.1+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-geckodriver-77.0.1-build1-0ubuntu0.20.04.1.md) | Jun 2, 2020 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 77.0.1+build1-0ubuntu0.18.04.1 | [firefox-mozsymbols 77.0.1+build1-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-77.0.1-build1-0ubuntu0.18.04.1.md) | Jun 2, 2020 |
| Linux | firefox-mozsymbols Ubuntu 20.04 LTS (focal) | 77.0.1+build1-0ubuntu0.20.04.1 | [firefox-mozsymbols 77.0.1+build1-0ubuntu0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-firefox-mozsymbols-77.0.1-build1-0ubuntu0.20.04.1.md) | Jun 2, 2020 |

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