# CVE-2018-12393: firefox: A potential vulnerability was found in 32-bit builds where an integer overflow during the conversion of scripts to an...

CVE-2018-12393 is fixed in 12 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-2018-12393
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0392
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 23, 2018

## Description

A potential vulnerability was found in 32-bit builds where an integer overflow during the conversion of scripts to an internal UTF-16 representation could result in allocating a buffer too small for the conversion. This leads to a possible out-of-bounds write. *Note: 64-bit builds are not vulnerable to this issue.*. This vulnerability affects Firefox < 63, Firefox ESR < 60.3, and Thunderbird < 60.3.

## 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 |
| Linux | thunderbird Ubuntu 18.04.6 LTS (bionic) | 1:60.4.0+build2-0ubuntu0.18.04.1 | [thunderbird 1:60.4.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-1-60.4.0-build2-0ubuntu0.18.04.1.md) | Jan 23, 2019 |
| Linux | thunderbird-globalmenu Ubuntu 18.04.6 LTS (bionic) | 1:60.4.0+build2-0ubuntu0.18.04.1 | [thunderbird-globalmenu 1:60.4.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-globalmenu-1-60.4.0-build2-0ubuntu0.18.04.1.md) | Jan 23, 2019 |
| Linux | thunderbird-gnome-support Ubuntu 18.04.6 LTS (bionic) | 1:60.4.0+build2-0ubuntu0.18.04.1 | [thunderbird-gnome-support 1:60.4.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-gnome-support-1-60.4.0-build2-0ubuntu0.18.04.1.md) | Jan 23, 2019 |
| Linux | thunderbird-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 1:60.4.0+build2-0ubuntu0.18.04.1 | [thunderbird-mozsymbols 1:60.4.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-mozsymbols-1-60.4.0-build2-0ubuntu0.18.04.1.md) | Jan 23, 2019 |
| Linux | thunderbird-testsuite Ubuntu 18.04.6 LTS (bionic) | 1:60.4.0+build2-0ubuntu0.18.04.1 | [thunderbird-testsuite 1:60.4.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-thunderbird-testsuite-1-60.4.0-build2-0ubuntu0.18.04.1.md) | Jan 23, 2019 |
| Linux | xul-ext-calendar-timezones Ubuntu 18.04.6 LTS (bionic) | 1:60.4.0+build2-0ubuntu0.18.04.1 | [xul-ext-calendar-timezones 1:60.4.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-calendar-timezones-1-60.4.0-build2-0ubuntu0.18.04.1.md) | Jan 23, 2019 |
| Linux | xul-ext-gdata-provider Ubuntu 18.04.6 LTS (bionic) | 1:60.4.0+build2-0ubuntu0.18.04.1 | [xul-ext-gdata-provider 1:60.4.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-gdata-provider-1-60.4.0-build2-0ubuntu0.18.04.1.md) | Jan 23, 2019 |
| Linux | xul-ext-lightning Ubuntu 18.04.6 LTS (bionic) | 1:60.4.0+build2-0ubuntu0.18.04.1 | [xul-ext-lightning 1:60.4.0+build2-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-xul-ext-lightning-1-60.4.0-build2-0ubuntu0.18.04.1.md) | Jan 23, 2019 |

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