What it is
CVE-2016-4656 is an unauthenticated vulnerability affecting Apple iOS. The kernel in Apple iOS before 9.3.5 allows attackers to execute arbitrary code in a privileged context or cause a denial of service (memory...
Vulnerability report
iOS Denial of Service
Apple / iOS
Decision summary
Direct answers before the deeper technical record.
What it is
CVE-2016-4656 is an unauthenticated vulnerability affecting Apple iOS. The kernel in Apple iOS before 9.3.5 allows attackers to execute arbitrary code in a privileged context or cause a denial of service (memory...
Is it exploited?
Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is confirmed.
Who is affected?
Apple / iOS.
What should we do?
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
Overview
The kernel in Apple iOS before 9.3.5 allows attackers to execute arbitrary code in a privileged context or cause a denial of service (memory corruption) via a crafted app.
Exploitation evidence
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
CISA
Independent exploitation attestation added to the KEV Intelligence record.
Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CISA First | 2022-05-24 00:00 UTC |
Detection
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Raw values available in Pro and Enterprise.
Metasploit template detected 28 Apr 2025.
View Metasploit template (opens in new tab)No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →Scanner and exploit-framework references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Metasploit | https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/apple_ios/browser/webkit_trident.rb | 28 Apr 2025 |
Risk and context
CVSS v3.1
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
21.3%
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
AV:N/AC:M/Au:N/C:C/I:C/A:C
Timeline
Exploit module available
Listed in the CISA Known Exploited Vulnerabilities catalog
Vulnerability disclosed publicly
Identifier reserved by the CNA
Pro API
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
GET /api/v2/pro/kevs/CVE-2016-4656
Free JSON includes basic KEV fields{
"cve_id": "CVE-2016-4656",
"confidence": "Confirmed",
"cvss_score": 7.8,
"cvss_estimated": false,
"epss_score": 0.21341,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "attempts": 0, "sensors": 0 }
}
Early warning alerts
Receive curator-selected alerts when exploitation activity warrants attention. Each alert includes the evidence and context needed to decide what requires attention now.