CVE-2016-2830: Infoleak

Published Jun 6, 2016
·
Updated

Last updated 24 July 2024

Other sources

Mozilla Firefox before 48.0 and Firefox ESR 45.x before 45.3 preserve the network connection used for favicon resource retrieval after the associated browser window is closed, which makes it easier for remote web servers to track users by observing network traffic from multiple IP addresses.

Launchpad

Security researcher Toni Huttunen reported that once the favicon is requested from a site, the favicon network connection will persist even when the page is later closed. This allows a malicious site to continue to use this channel to send requests to the browser, leading to potential information disclosure, such as the IP address of the user.

External Reference:

https://www.mozilla.org/security/announce/2016/mfsa2016-63.html

Acknowledgements:

Name: the Mozilla project Upstream: Toni Huttunen

Red Hat

Affected Software

11 affected componentsFixes available
Mozilla Firefox<=47.0.1
Mozilla Firefox=45.1.0
Mozilla Firefox=45.1.1
Mozilla Firefox=45.2.0
Mozilla Firefox=45.3.0
Mozilla Firefox ESR=45.1.0
Mozilla Firefox ESR=45.1.1
Mozilla Firefox ESR=45.2.0
Mozilla Firefox ESR=45.3.0
debian/firefox
137.0-1
debian/firefox-esr
115.14.0esr-1~deb11u1128.9.0esr-1~deb11u1128.8.0esr-1~deb12u1128.9.0esr-1~deb12u1128.8.0esr-1128.9.0esr-2

Event History

Jun 6, 2016
Data Sourced
via Red Hat·04:17 AM
DescriptionSeverityAffected Software
Aug 5, 2016
CVE Published
via MITRE·01:00 AM
Data Sourced
via MITRE·01:00 AM
Description
Jan 11, 2024
Data Sourced
via Launchpad·10:16 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·01:14 AM
RemedyDescriptionSeverityAffected Software
Mar 27, 2025
Data Sourced
via Debian·03:23 AM
DescriptionAffected Software

Frequently Asked Questions

1

What is CVE-2016-2830?

CVE-2016-2830 is a vulnerability in Mozilla Firefox and Firefox ESR that allows remote web servers to track users by observing network traffic from multiple IP addresses.

2

What is the severity of CVE-2016-2830?

The severity of CVE-2016-2830 is medium with a severity value of 4.3.

3

How does CVE-2016-2830 work?

CVE-2016-2830 allows the network connection used for favicon resource retrieval to be preserved even after the associated browser window is closed, making it easier for remote web servers to track users.

4

Which versions of Mozilla Firefox and Firefox ESR are affected by CVE-2016-2830?

Mozilla Firefox versions up to 47.0.1 and Firefox ESR versions 45.x before 45.3 are affected by CVE-2016-2830.

5

How can I fix CVE-2016-2830?

To fix CVE-2016-2830, update your Mozilla Firefox to version 48.0 or later, or update your Firefox ESR to version 45.3 or later.

Contact

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