CVE-2019-11757: Use After Free

Published Oct 22, 2019
·
Updated

A use-after-free flaw was found in Mozilla Firefox and Thunderbird. When following a value's prototype chain, it was possible to retain a reference to a locale, delete it, and subsequently reference it. An attacker could use this flaw to execute code that was stored in the referenced memory or crash the system.

Other sources

When following the value's prototype chain, it was possible to retain a reference to a locale, delete it, and subsequently reference it. This resulted in a use-after-free and a potentially exploitable crash.

Mozilla

When storing a value in IndexedDB, the value's prototype chain is followed and it was possible to retain a reference to a locale, delete it, and subsequently reference it. This resulted in a use-after-free and a potentially exploitable crash.

Mozilla

Affected Software

18 affected componentsFixes available
redhat/firefox<0:68.2.0-4.el6_10
0:68.2.0-4.el6_10
redhat/thunderbird<0:68.2.0-2.el6_10
0:68.2.0-2.el6_10
redhat/firefox<0:68.2.0-1.el7_7
0:68.2.0-1.el7_7
redhat/thunderbird<0:68.2.0-1.el7_7
0:68.2.0-1.el7_7
redhat/firefox<0:68.2.0-2.el8_0
0:68.2.0-2.el8_0
redhat/thunderbird<0:68.2.0-1.el8_0
0:68.2.0-1.el8_0
redhat/firefox<68.2
68.2
redhat/thunderbird<68.2
68.2
Mozilla Firefox<70.0
Mozilla Firefox ESR<68.2
Mozilla Thunderbird<68.2
Canonical Ubuntu Linux=16.04
Mozilla Thunderbird<68.2
68.2
Mozilla Firefox ESR<68.2
68.2
Mozilla Firefox<70
70
debian/firefox
148.0.2-1
debian/firefox-esr
115.14.0esr-1~deb11u1140.8.0esr-1~deb11u1128.14.0esr-1~deb12u1140.8.0esr-1~deb12u1140.4.0esr-1~deb13u1140.8.0esr-1~deb13u1140.8.0esr-1
debian/thunderbird
1:115.12.0-1~deb11u11:140.8.0esr-1~deb11u11:140.6.0esr-1~deb12u11:140.8.0esr-1~deb12u11:140.6.0esr-1~deb13u11:140.8.0esr-1~deb13u11:140.8.0esr-1

Event History

Oct 22, 2019
CVE Published
12:00 AM
Jan 8, 2020
CVE Published
via MITRE·07:26 PM
Data Sourced
via MITRE·07:26 PM
DescriptionWeakness
Jan 11, 2024
Data Sourced
via Launchpad·11:14 PM
Description
Feb 20, 2026
Data Sourced
via Ubuntu·08:34 PM
RemedyDescriptionSeverityAffected Software
Mar 11, 2026
Data Sourced
via Debian·08:48 PM
DescriptionAffected Software
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Frequently Asked Questions

1

What is vulnerability CVE-2019-11757?

Vulnerability CVE-2019-11757 is a use-after-free flaw found in Mozilla Firefox and Thunderbird.

2

What is the severity of vulnerability CVE-2019-11757?

The severity of vulnerability CVE-2019-11757 is high with a severity value of 8.8.

3

Which software is affected by vulnerability CVE-2019-11757?

Vulnerability CVE-2019-11757 affects Mozilla Firefox and Thunderbird versions 68.2.0-4.el6_10, 68.2.0-2.el6_10, 68.2.0-1.el7_7, 68.2.0-1.el8_0, and Firefox ESR 68.2.

4

How can an attacker exploit vulnerability CVE-2019-11757?

An attacker can exploit vulnerability CVE-2019-11757 to execute code stored in referenced memory or cause a crash.

5

Where can I find more information about vulnerability CVE-2019-11757?

You can find more information about vulnerability CVE-2019-11757 in the following references: [Reference 1](https://bugzilla.mozilla.org/show_bug.cgi?id=1577107), [Reference 2](https://www.mozilla.org/en-US/security/advisories/mfsa2019-33/), [Reference 3](https://www.mozilla.org/en-US/security/advisories/mfsa2019-35/).

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