CVE-2019-9794: Critical severity firefox vulnerability

Published Mar 19, 2019
·
Updated

A vulnerability was discovered where specific command line arguments are not properly discarded during Firefox invocation as a shell handler for URLs. This could be used to retrieve and execute files whose location is supplied through these command line arguments if Firefox is configured as the default URI handler for a given URI scheme in third party applications and these applications insufficiently sanitize URL data. Note: This issue only affects Windows operating systems. Other operating systems are unaffected.

Other sources

A vulnerability was discovered where specific command line arguments are not properly discarded during Firefox invocation as a shell handler for URLs. This could be used to retrieve and execute files whose location is supplied through these command line arguments if Firefox is configured as the default URI handler for a given URI scheme in third party applications and these applications insufficiently sanitize URL data. Note: This issue only affects Windows operating systems. Other operating systems are unaffected.. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

Affected Software

11 affected componentsFixes available
Mozilla Firefox<66
66
Mozilla Thunderbird<60.6
60.6
Mozilla Firefox ESR<60.6
60.6
Mozilla Firefox<66.0
Mozilla Firefox ESR<60.6.0
Mozilla Thunderbird<60.6.0
Microsoft Windows
All of the following
Any of the following
Mozilla Firefox<60.6.0
Mozilla Firefox<66.0
Mozilla Thunderbird<60.6.0
Microsoft Windows

Event History

Mar 19, 2019
CVE Published
via Mozilla·12:00 AM
Apr 26, 2019
CVE Published
via MITRE·04:13 PM
Data Sourced
via MITRE·04:13 PM
DescriptionWeakness
Data Sourced
via NVD·05:29 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the vulnerability ID for this vulnerability?

The vulnerability ID for this vulnerability is CVE-2019-9794.

2

What is the severity level of CVE-2019-9794?

The severity level of CVE-2019-9794 is critical.

3

Which software products are affected by CVE-2019-9794?

The software products affected by CVE-2019-9794 are Mozilla Firefox (version up to exclusive 66), Mozilla Thunderbird (version up to exclusive 60.6), and Mozilla Firefox ESR (version up to exclusive 60.6).

4

How can CVE-2019-9794 be exploited?

CVE-2019-9794 can be exploited by using specific command line arguments during Firefox invocation as a shell handler for URLs to retrieve and execute files.

5

Are Microsoft Windows systems vulnerable to CVE-2019-9794?

No, Microsoft Windows systems are not vulnerable to CVE-2019-9794.

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