CVE-2021-29977: High severity firefox vulnerability

Published Jul 13, 2021
·
Updated

Mozilla developers Andrew McCreight, Tyson Smith, Christian Holler, and Gabriele Svelto reported memory safety bugs present in Firefox 89. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

Other sources

Mozilla developers reported memory safety bugs present in Firefox 89. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 90.

Affected Software

2 affected componentsFixes available
Mozilla Firefox<90
90
Mozilla Firefox<90.0

Event History

Jul 13, 2021
CVE Published
12:00 AM
Aug 5, 2021
CVE Published
via MITRE·07:46 PM
Data Sourced
via MITRE·07:46 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-2021-29977?

CVE-2021-29977 has a high severity rating due to potential memory corruption that could allow for arbitrary code execution.

2

How do I fix CVE-2021-29977?

To fix CVE-2021-29977, update Mozilla Firefox to version 90 or later.

3

What versions of Firefox are affected by CVE-2021-29977?

CVE-2021-29977 affects Mozilla Firefox versions prior to 90.

4

Can CVE-2021-29977 be exploited remotely?

Yes, CVE-2021-29977 could potentially be exploited remotely if a user visits a specially crafted website.

5

Who reported CVE-2021-29977?

CVE-2021-29977 was reported by Mozilla developers Andrew McCreight, Tyson Smith, Christian Holler, and Gabriele Svelto.

Contact

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