CVE-2015-4478

CVE-2015-4478 is a medium-severity vulnerability in Mozilla Firefox with a CVSS 2.0 base score of 5.0. 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-200.

Key facts

Description

Mozilla Firefox before 40.0 and Firefox ESR 38.x before 38.2 do not impose certain ECMAScript 6 requirements on JavaScript object properties, which allows remote attackers to bypass the Same Origin Policy via the reviver parameter to the JSON.parse method.

Frequently asked questions

What is CVE-2015-4478?
Mozilla Firefox before 40.0 and Firefox ESR 38.x before 38.2 do not impose certain ECMAScript 6 requirements on JavaScript object properties, which allows remote attackers to bypass the Same Origin Policy via the reviver parameter to the JSON.parse method.
How severe is CVE-2015-4478?
CVE-2015-4478 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2015-4478 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2015-4478?
CVE-2015-4478 primarily affects Mozilla Firefox. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2015-4478?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2015-4478 published?
CVE-2015-4478 was published on 2015-08-16 and last updated on 2026-06-17.

References

Affected products (10)

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