CVE-2020-26973: High severity thunderbird vulnerability

Published Dec 15, 2020
·
Updated

Certain input to the CSS Sanitizer confused it, resulting in incorrect components being removed. This could have been used as a sanitizer bypass.

Affected Software

6 affected componentsFixes available
Mozilla Thunderbird<78.6
78.6
Mozilla Firefox<84.0
Mozilla Firefox ESR<78.6.0
Mozilla Thunderbird<78.6.0
Mozilla Firefox<84
84
Mozilla Firefox ESR<78.6
78.6

Event History

Dec 15, 2020
CVE Published
via Mozilla·12:00 AM
Jan 7, 2021
CVE Published
via MITRE·01:53 PM
Data Sourced
via MITRE·01:53 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2020-26973?

The severity of CVE-2020-26973 is categorized as moderate.

2

How do I fix CVE-2020-26973?

To fix CVE-2020-26973, update to Mozilla Firefox version 85 or later.

3

Which versions of Mozilla software are affected by CVE-2020-26973?

CVE-2020-26973 affects Mozilla Firefox versions prior to 85, Firefox ESR versions prior to 78.6, and Thunderbird versions prior to 78.6.

4

Can CVE-2020-26973 be exploited remotely?

Yes, CVE-2020-26973 can potentially be exploited remotely through crafted input.

5

What is the nature of the vulnerability in CVE-2020-26973?

CVE-2020-26973 is a sanitizer bypass vulnerability that confuses the CSS Sanitizer, leading to incorrect components being removed.

Contact

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