CVE-2017-7820: Medium severity firefox vulnerability

Published Sep 28, 2017
·
Updated

Last updated 24 July 2024

Other sources

The "instanceof" operator can bypass the Xray wrapper mechanism. When called on web content from the browser itself or an extension the web content can provide its own result for that operator, possibly tricking the browser or extension into mishandling the element. This vulnerability affects Firefox < 56.

Launchpad

The instanceof operator can bypass the Xray wrapper mechanism. When called on web content from the browser itself or an extension the web content can provide its own result for that operator, possibly tricking the browser or extension into mishandling the element.

Affected Software

3 affected componentsFixes available
debian/firefox
131.0.2-2
Mozilla Firefox<56
56
Mozilla Firefox<=55.0.3

Event History

Sep 28, 2017
CVE Published
12:00 AM
Jun 11, 2018
CVE Published
via MITRE·09:00 PM
Data Sourced
via MITRE·09:00 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·10:40 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·01:19 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the vulnerability ID?

The vulnerability ID is CVE-2017-7820.

2

Which software is affected by this vulnerability?

This vulnerability affects Mozilla Firefox versions up to and including 56.0.3.

3

What is the severity of CVE-2017-7820?

The severity of CVE-2017-7820 is medium, with a CVSS score of 5.3.

4

How can this vulnerability be exploited?

This vulnerability can be exploited by using the instanceof operator on web content from the browser itself or an extension, tricking the browser or extension into mishandling the element.

5

Is there a fix available for this vulnerability?

Yes, the vulnerability can be fixed by updating Mozilla Firefox to version 56.0.3 or newer.

Contact

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