CVE-2015-4520: Medium severity firefox vulnerability

Published Sep 24, 2015
·
Updated

Mozilla Firefox before 41.0 and Firefox ESR 38.x before 38.3 allow remote attackers to bypass CORS preflight protection mechanisms by leveraging (1) duplicate cache-key generation or (2) retrieval of a value from an incorrect HTTP Access-Control- response header.

Affected Software

15 affected components
Mozilla Firefox=38.0
Mozilla Firefox=38.0.1
Mozilla Firefox=38.0.5
Mozilla Firefox=38.1.0
Mozilla Firefox=38.1.1
Mozilla Firefox=38.2.0
Mozilla Firefox=38.2.1
Mozilla Firefox<=40.0.3
Mozilla Firefox ESR=38.0
Mozilla Firefox ESR=38.0.1
Mozilla Firefox ESR=38.0.5
Mozilla Firefox ESR=38.1.0
Mozilla Firefox ESR=38.1.1
Mozilla Firefox ESR=38.2.0
Mozilla Firefox ESR=38.2.1

Event History

Sep 24, 2015
CVE Published
via MITRE·01:00 AM
Data Sourced
via MITRE·01:00 AM
Description

Frequently Asked Questions

1

What is the severity of CVE-2015-4520?

CVE-2015-4520 has been assigned a medium severity level due to its potential to allow unauthorized access to resources.

2

How do I fix CVE-2015-4520?

To remediate CVE-2015-4520, users should update Mozilla Firefox to version 41.0 or later, or Firefox ESR to version 38.3 or later.

3

What is affected by CVE-2015-4520?

CVE-2015-4520 affects Mozilla Firefox versions before 41.0 and Firefox ESR versions before 38.3.

4

What types of attacks does CVE-2015-4520 allow?

CVE-2015-4520 allows remote attackers to bypass CORS preflight protections through method exploitation.

5

Who is impacted by CVE-2015-4520?

Users of vulnerable versions of Mozilla Firefox and Firefox ESR are at risk from CVE-2015-4520.

Contact

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