CVE-2021-29976: High severity firefox esr vulnerability

Published Jul 13, 2021
·
Updated

Mozilla developers Emil Ghitta, Tyson Smith, Valentin Gosu, Olli Pettay, and Randell Jesup reported memory safety bugs present in Firefox 89 and Firefox ESR 78.11. 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 code shared between Firefox and Thunderbird. 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 Thunderbird < 78.12, Firefox ESR < 78.12, and Firefox < 90.

Mozilla developers Valentin Gosu, Randell Jesup, Emil Ghitta, Tyson Smith, and Olli Pettay reported memory safety bugs present in Firefox 89 and Firefox ESR 78.11. 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.

Mozilla developers Valentin Gosu, Randell Jesup, Emil Ghitta, Tyson Smith, and Olli Pettay reported memory safety bugs present in Thunderbird 78.11. 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.

Mozilla

Affected Software

9 affected componentsFixes available
debian/firefox
118.0.2-1
debian/firefox-esr
91.12.0esr-1~deb10u1115.3.1esr-1~deb10u1102.15.0esr-1~deb11u1115.3.1esr-1~deb11u1102.15.1esr-1~deb12u1115.3.0esr-1~deb12u1115.3.0esr-1
debian/thunderbird
1:91.12.0-1~deb10u11:115.3.1-1~deb10u11:102.13.1-1~deb11u11:115.3.1-1~deb11u11:102.15.1-1~deb12u11:115.3.1-1~deb12u11:115.3.1-1
Mozilla Firefox ESR<78.12
78.12
Mozilla Thunderbird<78.12
78.12
Mozilla Firefox<90.0
Mozilla Firefox ESR<78.12
Mozilla Thunderbird<78.12
Mozilla Firefox<90
90

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-2021-29976?

CVE-2021-29976 is classified as a high-severity vulnerability due to potential memory corruption issues.

2

How do I fix CVE-2021-29976?

To fix CVE-2021-29976, update to Firefox version 90 or later, or Firefox ESR version 78.12 or later.

3

What products are affected by CVE-2021-29976?

CVE-2021-29976 affects Firefox 89, Firefox ESR 78.11, and earlier versions of these products.

4

Can CVE-2021-29976 be exploited?

Yes, although exploitation would require considerable effort due to memory safety issues involved.

5

Who reported CVE-2021-29976?

CVE-2021-29976 was reported by Mozilla developers Emil Ghitta, Tyson Smith, Valentin Gosu, Olli Pettay, and Randell Jesup.

Contact

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