CVE-2015-4520
First published: Thu 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.
Credit: security@mozilla.org security@mozilla.org
| Affected Software | Affected Version | How to fix |
|---|---|---|
| Firefox | =38.0 | |
| Firefox | =38.0.1 | |
| Firefox | =38.0.5 | |
| Firefox | =38.1.0 | |
| Firefox | =38.1.1 | |
| Firefox | =38.2.0 | |
| Firefox | =38.2.1 | |
| Firefox | <=40.0.3 | |
| Firefox ESR | =38.0 | |
| Firefox ESR | =38.0.1 | |
| Firefox ESR | =38.0.5 | |
| Firefox ESR | =38.1.0 | |
| Firefox ESR | =38.1.1 | |
| Firefox ESR | =38.2.0 | |
| Firefox ESR | =38.2.1 |
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Reference Links
- http://lists.opensuse.org/opensuse-security-announce/2015-10/msg00000.html
- http://lists.opensuse.org/opensuse-security-announce/2015-10/msg00003.html
- http://lists.opensuse.org/opensuse-security-announce/2015-10/msg00004.html
- http://lists.opensuse.org/opensuse-security-announce/2015-10/msg00005.html
- http://lists.opensuse.org/opensuse-security-announce/2015-10/msg00007.html
- http://lists.opensuse.org/opensuse-security-announce/2015-11/msg00025.html
- http://rhn.redhat.com/errata/RHSA-2015-1834.html
- http://rhn.redhat.com/errata/RHSA-2015-1852.html
- http://www.debian.org/security/2015/dsa-3365
- http://www.mozilla.org/security/announce/2015/mfsa2015-111.html
- http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
- http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
- http://www.securityfocus.com/bid/76816
- http://www.securitytracker.com/id/1033640
- http://www.ubuntu.com/usn/USN-2743-1
- http://www.ubuntu.com/usn/USN-2743-2
- http://www.ubuntu.com/usn/USN-2743-3
- http://www.ubuntu.com/usn/USN-2743-4
- http://www.ubuntu.com/usn/USN-2754-1
- https://bugzilla.mozilla.org/show_bug.cgi?id=1200856
- https://bugzilla.mozilla.org/show_bug.cgi?id=1200869
Frequently Asked Questions
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.
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.
What is affected by CVE-2015-4520?
CVE-2015-4520 affects Mozilla Firefox versions before 41.0 and Firefox ESR versions before 38.3.
What types of attacks does CVE-2015-4520 allow?
CVE-2015-4520 allows remote attackers to bypass CORS preflight protections through method exploitation.
Who is impacted by CVE-2015-4520?
Users of vulnerable versions of Mozilla Firefox and Firefox ESR are at risk from CVE-2015-4520.
- agent/type
- agent/weakness
- agent/severity
- agent/references
- agent/description
- collector/mitre-cve
- source/MITRE
- agent/first-publish-date
- agent/event
- agent/author
- agent/last-modified-date
- agent/source
- agent/tags
- agent/softwarecombine
- collector/nvd-api
- source/NVD
- agent/software-canonical-lookup
- agent/software-canonical-lookup-request
- collector/nvd-index
- vendor/mozilla
- canonical/firefox
- version/firefox/38.0
- version/firefox/38.0.1
- version/firefox/38.0.5
- version/firefox/38.1.0
- version/firefox/38.1.1
- version/firefox/38.2.0
- version/firefox/38.2.1
- version/firefox/40.0.3
- canonical/firefox esr
- version/firefox esr/38.0
- version/firefox esr/38.0.1
- version/firefox esr/38.0.5
- version/firefox esr/38.1.0
- version/firefox esr/38.1.1
- version/firefox esr/38.2.0
- version/firefox esr/38.2.1