CVE-2020-26953: Medium severity thunderbird vulnerability

Published Nov 17, 2020
·
Updated

It was possible to cause the browser to enter fullscreen mode without displaying the security UI; thus making it possible to attempt a phishing attack or otherwise confuse the user.

Affected Software

6 affected componentsFixes available
Mozilla Thunderbird<78.5
78.5
Mozilla Firefox<83.0
Mozilla Firefox ESR<78.5
Mozilla Thunderbird<78.5
Mozilla Firefox<83
83
Mozilla Firefox ESR<78.5
78.5

Event History

Nov 17, 2020
CVE Published
12:00 AM
Dec 9, 2020
CVE Published
via MITRE·12:20 AM
Data Sourced
via MITRE·12:20 AM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the vulnerability ID for this issue?

The vulnerability ID for this issue is CVE-2020-26953.

2

What is the severity of CVE-2020-26953?

CVE-2020-26953 has a severity level of medium (4).

3

Which software versions are affected by CVE-2020-26953?

The affected software versions are Mozilla Firefox ESR up to version 78.5, Mozilla Firefox up to version 83, and Mozilla Thunderbird up to version 78.5.

4

What is the description of CVE-2020-26953?

CVE-2020-26953 allows attackers to cause the browser to enter fullscreen mode without displaying the security UI, potentially leading to phishing attacks or user confusion.

5

How can I fix CVE-2020-26953?

To fix CVE-2020-26953, ensure you update your Mozilla Firefox ESR to version 78.5, Mozilla Firefox to version 83, or Mozilla Thunderbird to version 78.5.

Contact

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