CVE-2013-0756
CVE-2013-0756 is a critical-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 9.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.
Key facts
- Severity: Critical (CVSS 2.0 base score 9.3)
- EPSS exploit prediction: 4% (90th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-416
- Affected product: Mozilla Firefox
- Published:
- Last modified:
Description
Use-after-free vulnerability in the obj_toSource function in Mozilla Firefox before 18.0, Firefox ESR 17.x before 17.0.2, Thunderbird before 17.0.2, Thunderbird ESR 17.x before 17.0.2, and SeaMonkey before 2.15 allows remote attackers to execute arbitrary code via a crafted web page referencing JavaScript Proxy objects that are not properly handled during garbage collection.
Frequently asked questions
- What is CVE-2013-0756?
- Use-after-free vulnerability in the obj_toSource function in Mozilla Firefox before 18.0, Firefox ESR 17.x before 17.0.2, Thunderbird before 17.0.2, Thunderbird ESR 17.x before 17.0.2, and SeaMonkey before 2.15 allows remote attackers to execute arbitrary code via a crafted web page referencing JavaScript Proxy objects that are not properly handled during garbage collection.
- How severe is CVE-2013-0756?
- CVE-2013-0756 has a CVSS 2.0 base score of 9.3, rated critical severity.
- Is CVE-2013-0756 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2013-0756?
- CVE-2013-0756 primarily affects Mozilla Firefox. In total, 18 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2013-0756?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2013-0756 published?
- CVE-2013-0756 was published on 2013-01-13 and last updated on 2026-06-16.
References
- http://lists.opensuse.org/opensuse-security-announce/2013-01/msg00006.html
- http://lists.opensuse.org/opensuse-security-announce/2013-01/msg00007.html
- http://lists.opensuse.org/opensuse-security-announce/2013-01/msg00010.html
- http://lists.opensuse.org/opensuse-security-announce/2013-01/msg00017.html
- http://www.mozilla.org/security/announce/2013/mfsa2013-19.html
- http://www.ubuntu.com/usn/USN-1681-1
- http://www.ubuntu.com/usn/USN-1681-2
- http://www.ubuntu.com/usn/USN-1681-4
- https://bugzilla.mozilla.org/show_bug.cgi?id=814029
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A17101
Affected products (18)
- cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:seamonkey:*:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*
- cpe:2.3:a:mozilla:thunderbird_esr:*:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:opensuse:11.4:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:opensuse:12.1:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:opensuse:12.2:*:*:*:*:*:*:*
- cpe:2.3:o:suse:linux_enterprise_desktop:10:sp4:*:*:*:*:*:*
- cpe:2.3:o:suse:linux_enterprise_desktop:11:sp2:*:*:*:*:*:*
- cpe:2.3:o:suse:linux_enterprise_server:10:sp4:*:*:*:*:*:*
- cpe:2.3:o:suse:linux_enterprise_server:11:sp2:*:*:*:-:*:*
- cpe:2.3:o:suse:linux_enterprise_server:11:sp2:*:*:*:vmware:*:*
- cpe:2.3:o:suse:linux_enterprise_software_development_kit:10:sp4:*:*:*:*:*:*
- cpe:2.3:o:suse:linux_enterprise_software_development_kit:11:sp2:*:*:*:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:10.04:*:*:*:-:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:11.10:*:*:*:*:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:12.10:*:*:*:*:*:*:*
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