CVE-2023-5171: Use After Free

Published Sep 26, 2023
·
Updated

During Ion compilation, a Garbage Collection could have resulted in a use-after-free condition, allowing an attacker to write two NUL bytes, and cause a potentially exploitable crash.

Affected Software

14 affected componentsFixes available
redhat/firefox<115.3
115.3
Mozilla Thunderbird<115.3
115.3
Mozilla Firefox<118
118
Mozilla Firefox ESR<115.3
115.3
Mozilla Firefox<118
Mozilla Firefox ESR<115.3
Mozilla Thunderbird<115.3
Debian Debian Linux=10.0
Debian Debian Linux=11.0
Debian Debian Linux=12.0
Fedoraproject Fedora=39
debian/firefox
138.0.1-1
debian/firefox-esr
115.14.0esr-1~deb11u1128.9.0esr-1~deb11u1128.8.0esr-1~deb12u1128.10.0esr-1~deb12u1128.10.0esr-1
debian/thunderbird
1:115.12.0-1~deb11u11:128.10.0esr-1~deb11u11:128.8.0esr-1~deb12u11:128.10.0esr-1~deb12u11:128.10.0esr-1

Event History

Sep 26, 2023
CVE Published
via Mozilla·12:00 AM
Sep 27, 2023
CVE Published
via MITRE·02:13 PM
Data Sourced
via MITRE·02:13 PM
DescriptionWeakness
Jan 12, 2024
Data Sourced
via Launchpad·12:28 AM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·04:18 AM
RemedyDescriptionSeverityAffected Software
Feb 27, 2025
Data Sourced
via Debian·02:04 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2023-5171?

CVE-2023-5171 is a vulnerability that occurs during Ion compilation in Mozilla Firefox and Thunderbird, allowing an attacker to cause a potentially exploitable crash.

2

What is the severity of CVE-2023-5171?

CVE-2023-5171 has a severity level of high (7).

3

Which software products are affected by CVE-2023-5171?

The affected software products are Mozilla Firefox ESR up to version 115.3, Mozilla Firefox up to version 118, and Mozilla Thunderbird up to version 115.3.

4

How can an attacker exploit CVE-2023-5171?

An attacker can exploit CVE-2023-5171 by triggering a Garbage Collection during Ion compilation, resulting in a use-after-free condition.

5

Is there a remedy available for CVE-2023-5171?

The remedy for CVE-2023-5171 is to update Mozilla Firefox ESR to version 115.3 or later, Mozilla Firefox to version 118 or later, and Mozilla Thunderbird to version 115.3 or later.

Contact

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