CVE-2020-12391: High severity firefox vulnerability

Published May 5, 2020
·
Updated

Documents formed using data: URLs in an OBJECT element failed to inherit the CSP of the creating context. This allowed the execution of scripts that should have been blocked, albeit with a unique opaque origin. This vulnerability affects Firefox < 76.

Affected Software

16 affected componentsFixes available
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0+
76.0+
ubuntu/firefox<76.0
76.0
ubuntu/firefox<76.0+
76.0+
debian/firefox
130.0-2
Mozilla Firefox<76
76
Mozilla Firefox<76.0

Event History

May 5, 2020
CVE Published
12:00 AM
May 26, 2020
CVE Published
via MITRE·05:02 PM
Data Sourced
via MITRE·05:02 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:37 PM
Description

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2020-12391?

CVE-2020-12391 is classified as a moderate severity vulnerability.

2

How do I fix CVE-2020-12391?

To fix CVE-2020-12391, users should update to Mozilla Firefox version 76 or later.

3

What versions of Firefox are affected by CVE-2020-12391?

CVE-2020-12391 affects all versions of Mozilla Firefox prior to version 76.

4

What is the impact of CVE-2020-12391?

CVE-2020-12391 allows execution of blocked scripts through data: URLs in an OBJECT element.

5

Does CVE-2020-12391 affect other browsers apart from Firefox?

CVE-2020-12391 specifically affects Firefox and is not reported to impact other major browsers.

Contact

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