CVE-2019-9809: High severity firefox vulnerability

Published Mar 19, 2019
·
Updated

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.

Affected Software

3 affected componentsFixes available
Mozilla Firefox<66
66
Mozilla Firefox<66.0
debian/firefox
137.0-1

Event History

Mar 19, 2019
CVE Published
12:00 AM
Apr 26, 2019
CVE Published
via MITRE·04:10 PM
Data Sourced
via MITRE·04:10 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:33 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·02:18 AM
RemedyDescriptionSeverityAffected Software
Mar 27, 2025
Data Sourced
via Debian·04:11 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2019-9809?

CVE-2019-9809 is a vulnerability that allows for a denial of service (DOS) attack by triggering a series of modal alert messages through invalid credentials or locations when the source for resources on a page is through an FTP connection.

2

Which software is affected by CVE-2019-9809?

Mozilla Firefox versions up to and excluding 66.0, as well as Ubuntu and Debian packages of Firefox versions up to and excluding 66.0, are affected by CVE-2019-9809.

3

What is the severity of CVE-2019-9809?

CVE-2019-9809 has a severity rating of high with a CVSS score of 7.5.

4

How can I fix CVE-2019-9809?

To fix CVE-2019-9809, upgrade to Mozilla Firefox version 66.0 or later, or update your Ubuntu or Debian Firefox package to version 66.0 or later.

5

Where can I find more information about CVE-2019-9809?

More information about CVE-2019-9809 can be found at the following references: [Bugzilla #1282430](https://bugzilla.mozilla.org/show_bug.cgi?id=1282430), [Bugzilla #1523249](https://bugzilla.mozilla.org/show_bug.cgi?id=1523249), [Mozilla Security Advisories MFSB2019-07](https://www.mozilla.org/en-US/security/advisories/mfsa2019-07/).

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