# CVE-2018-12396: firefox-testsuite: A vulnerability where a WebExtension can run content scripts in disallowed contexts following navigation or other events

CVE-2018-12396 is fixed in 4 products on 1 platform, first by firefox 63.0+build2-0ubuntu0.18.04.2, released October 23, 2018. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2018-12396
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0227
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 23, 2018

## Description

A vulnerability where a WebExtension can run content scripts in disallowed contexts following navigation or other events. This allows for potential privilege escalation by the WebExtension on sites where content scripts should not be run. This vulnerability affects Firefox ESR < 60.3 and Firefox < 63.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 63.0+build2-0ubuntu0.18.04.2 | [firefox 63.0+build2-0ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-63.0-build2-0ubuntu0.18.04.2.md) | Oct 23, 2018 |
| Linux | firefox-globalmenu Ubuntu 18.04.6 LTS (bionic) | 63.0+build2-0ubuntu0.18.04.2 | [firefox-globalmenu 63.0+build2-0ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-globalmenu-63.0-build2-0ubuntu0.18.04.2.md) | Oct 23, 2018 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 63.0+build2-0ubuntu0.18.04.2 | [firefox-mozsymbols 63.0+build2-0ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-63.0-build2-0ubuntu0.18.04.2.md) | Oct 23, 2018 |
| Linux | firefox-testsuite Ubuntu 18.04.6 LTS (bionic) | 63.0+build2-0ubuntu0.18.04.2 | [firefox-testsuite 63.0+build2-0ubuntu0.18.04.2](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-testsuite-63.0-build2-0ubuntu0.18.04.2.md) | Oct 23, 2018 |

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