CVE-2020-26974: Use After Free

Published Dec 15, 2020
·
Updated

When flex-basis was used on a table wrapper, a StyleGenericFlexBasis object could have been incorrectly cast to the wrong type. This resulted in a heap user-after-free, memory corruption, and a potentially exploitable crash.

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·01:52 PM
Data Sourced
via MITRE·01:52 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-2020-26974?

CVE-2020-26974 is considered a critical vulnerability due to its potential for memory corruption and exploitable crashes.

2

How do I fix CVE-2020-26974?

To mitigate CVE-2020-26974, users should update Mozilla Firefox, Firefox ESR, or Thunderbird to versions 84 and 78.6 or later.

3

What types of software are affected by CVE-2020-26974?

CVE-2020-26974 affects Mozilla Firefox, Firefox ESR, and Thunderbird versions below specified thresholds.

4

Can CVE-2020-26974 lead to remote code execution?

While CVE-2020-26974 may cause a crash, it has not been confirmed to directly lead to remote code execution.

5

Is CVE-2020-26974 exploitable by attackers?

Yes, CVE-2020-26974 could potentially be exploited by attackers to cause crashes and disrupt service.

Contact

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