CVE-2019-11691: Use After Free

Published May 21, 2019
·
Updated

A use-after-free vulnerability can occur when working with XMLHttpRequest (XHR) in an event loop, causing the XHR main thread to be called after it has been freed. This results in a potentially exploitable crash.

External Reference:

https://www.mozilla.org/en-US/security/advisories/mfsa2019-14/#CVE-2019-11691

Other sources

A use-after-free vulnerability can occur when working with XMLHttpRequest (XHR) in an event loop, causing the XHR main thread to be called after it has been freed. This results in a potentially exploitable crash.

— Mozilla

Affected Software

24 affected componentsFixes available
Mozilla Thunderbird<60.7
60.7
Mozilla Firefox<67.0
Mozilla Firefox ESR<60.7
Mozilla Thunderbird<60.7
Mozilla Firefox<67
67
Mozilla Firefox ESR<60.7
60.7
debian/firefox
159.0-1
debian/firefox-esr
140.12.0esr-1~deb12u1153.6.0esr-1~deb12u2140.15.0esr-1~deb13u1153.6.0esr-1~deb13u1153.5.1esr-1153.6.0esr-1
debian/thunderbird
1:140.12.0esr-1~deb12u11:153.6.0esr-1~deb12u21:140.12.0esr-1~deb13u11:153.6.0esr-1~deb13u11:153.5.0esr-11:153.6.0esr-1
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0
alpine/firefox-esr<60.7.0-r0
60.7.0-r0

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 159.0-1
  5. Upgrade

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

    Fixed in 140.12.0esr-1~deb12u1Fixed in 153.6.0esr-1~deb12u2Fixed in 140.15.0esr-1~deb13u1Fixed in 153.6.0esr-1~deb13u1Fixed in 153.5.1esr-1Fixed in 153.6.0esr-1
  6. Upgrade

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

    Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:153.6.0esr-1~deb12u2Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:153.6.0esr-1~deb13u1Fixed in 1:153.5.0esr-1Fixed in 1:153.6.0esr-1

Event History

May 21, 2019
CVE Published
12:00 AM
May 22, 2019
Data Sourced
via Red Hat·01:41 AM
DescriptionSeverityAffected Software
Jul 23, 2019
CVE Published
via MITRE·01:23 PM
Data Sourced
via MITRE·01:23 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 CVE-2019-11691?

CVE-2019-11691 is a use-after-free vulnerability that can occur when working with XMLHttpRequest (XHR) in an event loop, causing a potentially exploitable crash in Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

2

How does CVE-2019-11691 affect Mozilla Firefox?

CVE-2019-11691 affects Mozilla Firefox versions up to exclusive 67.

3

How does CVE-2019-11691 affect Mozilla Firefox ESR?

CVE-2019-11691 affects Mozilla Firefox ESR versions up to exclusive 60.7.

4

How does CVE-2019-11691 affect Thunderbird?

CVE-2019-11691 affects Thunderbird versions up to exclusive 60.7.

5

What is the severity of CVE-2019-11691?

The severity of CVE-2019-11691 is critical, with a CVSS score of 9.8.

Company

Resources

Contact

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