CVE-2017-7761: Medium severity firefox vulnerability

Published Jun 13, 2017
·
Updated

The Mozilla Maintenance Service helper.exe application creates a temporary directory writable by non-privileged users. When this is combined with creation of a junction (a form of symbolic link), protected files in the target directory of the junction can be deleted by the Mozilla Maintenance Service, which has privileged access. Note: This attack requires local system access and only affects Windows. Other operating systems are not affected.

Other sources

The Mozilla Maintenance Service "helper.exe" application creates a temporary directory writable by non-privileged users. When this is combined with creation of a junction (a form of symbolic link), protected files in the target directory of the junction can be deleted by the Mozilla Maintenance Service, which has privileged access. Note: This attack requires local system access and only affects Windows. Other operating systems are not affected. This vulnerability affects Firefox ESR < 52.2 and Firefox < 54.

Affected Software

8 affected componentsFixes available
Mozilla Firefox<54
54
Mozilla Firefox ESR<52.2
52.2
Mozilla Firefox<54.0
Mozilla Firefox ESR<52.2.0
Microsoft Windows
All of the following
Any of the following
Mozilla Firefox<52.2.0
Mozilla Firefox<54.0
Microsoft Windows

Event History

Jun 13, 2017
CVE Published
via Mozilla·12:00 AM
Jun 11, 2018
CVE Published
via MITRE·09:00 PM
Data Sourced
via MITRE·09:00 PM
DescriptionWeakness
Data Sourced
via NVD·09:29 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2017-7761?

CVE-2017-7761 is considered a moderate severity vulnerability.

2

How do I fix CVE-2017-7761?

To fix CVE-2017-7761, upgrade to Mozilla Firefox version 54 or later and Firefox ESR version 52.3 or later.

3

What causes CVE-2017-7761?

CVE-2017-7761 is caused by the Mozilla Maintenance Service creating a writable temporary directory that can be exploited by non-privileged users.

4

Which versions of Firefox are affected by CVE-2017-7761?

CVE-2017-7761 affects Firefox versions up to 54 and Firefox ESR versions up to 52.2.

5

Is my operating system affected by CVE-2017-7761?

CVE-2017-7761 specifically affects Mozilla Firefox and Firefox ESR running on Microsoft Windows.

Contact

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