# CVE-2019-9809: firefox: If the source for resources on a page is through an FTP connection, it is possible to trigger a series of modal alert...

CVE-2019-9809 is fixed in 4 products on 1 platform, first by firefox 66.0+build3-0ubuntu0.18.04.1, released March 19, 2019. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2019-9809
- Priority: Routine
- CVSS: n/a (Low)
- EPSS: 0.0164
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 19, 2019

## Description

If the source for resources on a page is through an FTP connection, it is possible to trigger a series of modal alert messages for these resources through invalid credentials or locations. These messages cannot be immediately dismissed, allowing for a denial of service (DOS) attack. This vulnerability affects Firefox < 66.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | firefox Ubuntu 18.04.6 LTS (bionic) | 66.0+build3-0ubuntu0.18.04.1 | [firefox 66.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-66.0-build3-0ubuntu0.18.04.1.md) | Mar 19, 2019 |
| Linux | firefox-globalmenu Ubuntu 18.04.6 LTS (bionic) | 66.0+build3-0ubuntu0.18.04.1 | [firefox-globalmenu 66.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-globalmenu-66.0-build3-0ubuntu0.18.04.1.md) | Mar 19, 2019 |
| Linux | firefox-mozsymbols Ubuntu 18.04.6 LTS (bionic) | 66.0+build3-0ubuntu0.18.04.1 | [firefox-mozsymbols 66.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-mozsymbols-66.0-build3-0ubuntu0.18.04.1.md) | Mar 19, 2019 |
| Linux | firefox-testsuite Ubuntu 18.04.6 LTS (bionic) | 66.0+build3-0ubuntu0.18.04.1 | [firefox-testsuite 66.0+build3-0ubuntu0.18.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-firefox-testsuite-66.0-build3-0ubuntu0.18.04.1.md) | Mar 19, 2019 |

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Data as of 2026-11-07T12:40:37Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo