CVE-2023-6205: Use After Free

Published Nov 21, 2023
·
Updated

It was possible to cause the use of a MessagePort after it had already been freed, which could potentially have led to an exploitable crash.

Affected Software

19 affected componentsFixes available
redhat/firefox<115.5
115.5
redhat/thunderbird<115.5
115.5
ubuntu/firefox<120.0+
120.0+
ubuntu/thunderbird<1:115.5.0+
1:115.5.0+
ubuntu/thunderbird<1:115.5.0+
1:115.5.0+
ubuntu/thunderbird<1:115.5.0+
1:115.5.0+
ubuntu/thunderbird<1:115.5.0+
1:115.5.0+
debian/firefox
123.0-1
debian/firefox-esr<=91.12.0esr-1~deb10u1
115.8.0esr-1~deb10u1115.7.0esr-1~deb11u1115.8.0esr-1~deb11u1115.7.0esr-1~deb12u1115.8.0esr-1~deb12u1115.8.0esr-1
debian/thunderbird<=1:91.12.0-1~deb10u1
1:115.8.0-1~deb10u11:115.7.0-1~deb11u11:115.8.0-1~deb11u11:115.7.0-1~deb12u11:115.8.0-1~deb12u11:115.7.0-11:115.8.1-1
Mozilla Thunderbird<115.5
115.5
Mozilla Firefox ESR<115.5
115.5
Mozilla Firefox<120
120
Mozilla Firefox<120.0
Mozilla Firefox ESR<115.5.0
Mozilla Thunderbird<115.5
Debian Debian Linux=10.0
Debian Debian Linux=11.0
Debian Debian Linux=12.0

Event History

Nov 21, 2023
CVE Published
via Ubuntu·12:00 AM
CVE Published
via MITRE·02:28 PM
Data Sourced
via MITRE·02:28 PM
DescriptionWeakness
Jan 12, 2024
Data Sourced
via Launchpad·12:28 AM
Description

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2023-6205?

CVE-2023-6205 is a vulnerability that allows the use of a MessagePort after it has been freed, potentially leading to an exploitable crash.

2

Which software is affected by CVE-2023-6205?

Mozilla Firefox versions prior to 120, Mozilla Firefox versions prior to 115.5, and Mozilla Thunderbird versions prior to 115.5.0 are affected by CVE-2023-6205.

3

What is the severity of CVE-2023-6205?

CVE-2023-6205 has a severity level of high (7 out of 10).

4

How can I fix CVE-2023-6205?

To fix CVE-2023-6205, update your Mozilla Firefox or Mozilla Thunderbird to the recommended versions: Firefox 120 or later, Firefox 115.5.0 or later, or Thunderbird 115.5.0 or later.

5

Where can I find more information about CVE-2023-6205?

You can find more information about CVE-2023-6205 in the following references: [Mozilla Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1854076), [Mozilla Security Advisories](https://www.mozilla.org/security/advisories/mfsa2023-49/), [Mozilla Security Advisories](https://www.mozilla.org/security/advisories/mfsa2023-50/).

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