CVE-2021-29966: High severity Mozilla Firefox vulnerability

Published Jun 1, 2021
·
Updated

Mozilla developers Christian Holler, Tooru Fujisawa, Tyson Smith reported memory safety bugs present in Firefox 88. 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 88. 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 < 89.

Affected Software

17 affected componentsFixes available
Mozilla Firefox<89
89
Mozilla Firefox>=78.11.0<89.0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/firefox>=78.11.0<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0
alpine/librewolf<89.0-r0
89.0-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 89
  2. Upgrade

    Upgrade alpine/firefox to a version that resolves this vulnerability.

    Fixed in 89.0-r0
  3. Upgrade

    Upgrade alpine/librewolf to a version that resolves this vulnerability.

    Fixed in 89.0-r0

Event History

Jun 1, 2021
CVE Published
12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:14 PM
Data Sourced
via MITRE·01:14 PM
DescriptionWeakness
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·02:15 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2021-29966?

CVE-2021-29966 is classified as a high-severity vulnerability that could potentially allow for arbitrary code execution due to memory corruption issues in Firefox 88.

2

How do I fix CVE-2021-29966?

To fix CVE-2021-29966, users should upgrade to Mozilla Firefox version 89 or later.

3

What versions of Firefox are affected by CVE-2021-29966?

CVE-2021-29966 affects Mozilla Firefox versions from 78.11.0 up to, but not including, 89.

4

What type of vulnerability is CVE-2021-29966?

CVE-2021-29966 is a memory safety vulnerability that could lead to memory corruption.

5

Who reported CVE-2021-29966?

CVE-2021-29966 was reported by Mozilla developers Christian Holler, Tooru Fujisawa, and Tyson Smith.

Company

Resources

Contact

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