CVE-2016-1960

CVE-2016-1960 is a high-severity vulnerability in Mozilla Firefox with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 31% places it in the 98th percentile, indicating an elevated likelihood of exploitation.

Key facts

Description

Integer underflow in the nsHtml5TreeBuilder class in the HTML5 string parser in Mozilla Firefox before 45.0 and Firefox ESR 38.x before 38.7 allows remote attackers to execute arbitrary code or cause a denial of service (use-after-free) by leveraging mishandling of end tags, as demonstrated by incorrect SVG processing, aka ZDI-CAN-3545.

Frequently asked questions

What is CVE-2016-1960?
Integer underflow in the nsHtml5TreeBuilder class in the HTML5 string parser in Mozilla Firefox before 45.0 and Firefox ESR 38.x before 38.7 allows remote attackers to execute arbitrary code or cause a denial of service (use-after-free) by leveraging mishandling of end tags, as demonstrated by incorrect SVG processing, aka ZDI-CAN-3545.
How severe is CVE-2016-1960?
CVE-2016-1960 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2016-1960 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-1960?
CVE-2016-1960 primarily affects Mozilla Firefox. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-1960?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2016-1960 published?
CVE-2016-1960 was published on 2016-03-13 and last updated on 2026-06-17.

References

Affected products (22)

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