CVE-2023-6865: Medium severity firefox vulnerability

Published Dec 19, 2023
·
Updated

EncryptingOutputStream was susceptible to exposing uninitialized data. This issue could only be abused in order to write data to a local disk which may have implications for private browsing mode.

External Reference: https://www.mozilla.org/en-US/security/advisories/mfsa2023-54/#CVE-2023-6865

Other sources

EncryptingOutputStream was susceptible to exposing uninitialized data. This issue could only be abused in order to write data to a local disk which may have implications for private browsing mode. This vulnerability affects Firefox ESR < 115.6 and Firefox < 121.

MITRE

EncryptingOutputStream was susceptible to exposing uninitialized data. This issue could only be abused in order to write data to a local disk which may have implications for private browsing mode.

Mozilla

Affected Software

11 affected componentsFixes available
redhat/firefox<115.6
115.6
redhat/thunderbird<115.6
115.6
Mozilla Firefox<121
121
Mozilla Firefox ESR<115.6
115.6
Mozilla Firefox<121.0
Mozilla Firefox ESR<115.6
Debian Debian Linux=10.0
Debian Debian Linux=11.0
Debian Debian Linux=12.0
debian/firefox
137.0.2-1
debian/firefox-esr
115.14.0esr-1~deb11u1128.9.0esr-1~deb11u1128.8.0esr-1~deb12u1128.9.0esr-1~deb12u1128.9.0esr-2

Event History

Dec 19, 2023
CVE Published
via Mozilla·12:00 AM
CVE Published
via MITRE·01:38 PM
Data Sourced
via MITRE·01:38 PM
DescriptionWeakness
Dec 20, 2023
Data Sourced
via Red Hat·11:16 AM
DescriptionSeverityAffected Software
Jan 12, 2024
Data Sourced
via Launchpad·12:29 AM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·04:19 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2023-6865?

CVE-2023-6865 is considered a medium severity vulnerability due to potential data exposure in private browsing mode.

2

How do I fix CVE-2023-6865?

To fix CVE-2023-6865, update to Firefox version 121, or ensure you are using Firefox ESR version 115.14 or newer.

3

Which versions of Firefox are affected by CVE-2023-6865?

CVE-2023-6865 affects Firefox versions prior to 121 and Firefox ESR versions prior to 115.14.

4

Is CVE-2023-6865 present in Thunderbird?

Yes, CVE-2023-6865 affects Thunderbird versions up to 115.6.

5

Can CVE-2023-6865 be exploited remotely?

CVE-2023-6865 cannot be exploited remotely as it requires local write access.

Contact

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