CVE-2019-9820: Use After Free

Published May 21, 2019
·
Updated

A use-after-free vulnerability can occur in the chrome event handler when it is freed while still in use. This results in a potentially exploitable crash.

Affected Software

9 affected componentsFixes available
Mozilla Thunderbird<60.7
60.7
Mozilla Firefox<67.0
Mozilla Firefox ESR<60.7
Mozilla Thunderbird<60.7.0
Mozilla Firefox<67
67
Mozilla Firefox ESR<60.7
60.7
debian/firefox
152.0-1
debian/firefox-esr
115.14.0esr-1~deb11u1140.11.0esr-1~deb11u1140.10.2esr-1~deb12u1140.12.0esr-1~deb12u1140.10.2esr-1~deb13u1140.12.0esr-1~deb13u1140.11.0esr-1140.12.0esr-1
debian/thunderbird
1:115.12.0-1~deb11u11:140.12.0esr-1~deb11u11:140.10.1esr-1~deb12u11:140.11.0esr-1~deb12u11:140.10.1esr-1~deb13u11:140.11.0esr-1~deb13u11:140.11.0esr-11:140.12.0esr-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 60.7
  2. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 67
  3. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 60.7
  4. Upgrade

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

    Fixed in 152.0-1
  5. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 115.14.0esr-1~deb11u1Fixed in 140.11.0esr-1~deb11u1Fixed in 140.10.2esr-1~deb12u1Fixed in 140.12.0esr-1~deb12u1Fixed in 140.10.2esr-1~deb13u1Fixed in 140.12.0esr-1~deb13u1Fixed in 140.11.0esr-1Fixed in 140.12.0esr-1
  6. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:115.12.0-1~deb11u1Fixed in 1:140.12.0esr-1~deb11u1Fixed in 1:140.10.1esr-1~deb12u1Fixed in 1:140.11.0esr-1~deb12u1Fixed in 1:140.10.1esr-1~deb13u1Fixed in 1:140.11.0esr-1~deb13u1Fixed in 1:140.11.0esr-1Fixed in 1:140.12.0esr-1
  7. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 115.14.0esr-1~deb11u1
  8. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.11.0esr-1~deb11u1
  9. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.10.2esr-1~deb12u1
  10. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.12.0esr-1~deb12u1
  11. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.10.2esr-1~deb13u1
  12. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.12.0esr-1~deb13u1
  13. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.11.0esr-1
  14. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 140.12.0esr-1
  15. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:115.12.0-1~deb11u1
  16. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.12.0esr-1~deb11u1
  17. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.10.1esr-1~deb12u1
  18. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.11.0esr-1~deb12u1
  19. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.10.1esr-1~deb13u1
  20. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.11.0esr-1~deb13u1
  21. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.11.0esr-1
  22. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:140.12.0esr-1

Event History

May 21, 2019
CVE Published
via Mozilla·12:00 AM
May 22, 2019
Data Sourced
via Red Hat·01:47 AM
DescriptionSeverityAffected Software
Jul 23, 2019
CVE Published
via MITRE·01:23 PM
Data Sourced
via MITRE·01:23 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:34 PM
Description
Feb 19, 2026
Data Sourced
via Ubuntu·06:00 PM
RemedyDescriptionSeverityAffected Software
Jun 18, 2026
Data Sourced
via Debian·04:01 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is CVE-2019-9820?

CVE-2019-9820 is a use-after-free vulnerability that can occur in the chrome event handler when it is freed while still in use.

2

Which software products are affected by CVE-2019-9820?

CVE-2019-9820 affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

3

What is the severity of CVE-2019-9820?

CVE-2019-9820 has a severity rating of critical, with a CVSS score of 9.8.

4

How can I fix CVE-2019-9820 in Thunderbird?

To fix CVE-2019-9820 in Thunderbird, update to version 60.7.0 or higher.

5

How can I fix CVE-2019-9820 in Firefox?

To fix CVE-2019-9820 in Firefox, update to version 67.0 or higher.

6

How can I fix CVE-2019-9820 in Firefox ESR?

To fix CVE-2019-9820 in Firefox ESR, update to version 60.7.0 or higher.

Company

Resources

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