# CVE-2018-12399: firefox: When a new protocol handler is registered, the API accepts a title argument which can be used to mislead users about...

CVE-2018-12399 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-2018-12399
- Priority: Routine
- CVSS: n/a (Low)
- EPSS: 0.0157
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 23, 2018

## Description

When a new protocol handler is registered, the API accepts a title argument which can be used to mislead users about which domain is registering the new protocol. This may result in the user approving a protocol handler that they otherwise would not have. This vulnerability affects 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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