CVE-2016-2821

Status: ModifiedHigh (7.5)—
Use-after-free vulnerability in the mozilla::dom::Element class in Mozilla Firefox before 47.0 and Firefox ESR 45.x before 45.2, when contenteditable mode is enabled, allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) by triggering deletion of DOM elements that were created in the editor.
CVSS

Version: 3.0
Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Base score: 7.5
Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 2.77%
Percentile among all scored CVEs: 86
Score date: 10/10/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (5)

Canonical — Ubuntu Linux Debian — Debian Linux Mozilla — Firefox Opensuse — Leap Opensuse — Opensuse
CWEs

NVD-CWE-Other
References

Raw JSON (NVD)

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