What is the CVSS score of CVE-2016-4656?

CVE-2016-4656 has a CVSS 3.1 base score of 7.8 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. EPSS exploitation probability: 66.7%.

Is there a public PoC exploit available for CVE-2016-4656?

Yes, a public proof-of-concept exploit is available for CVE-2016-4656. Prioritise patching immediately. EPSS: 66.7%.

Apple CVE-2016-4656

HIGH

Out-of-bounds Write (CWE-787)

2016-08-25 product-security@apple.com

Buffer Overflow Memory Corruption Denial Of Service RCE Apple

7.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

7.8 HIGH

AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Added to CISA KEV

Apr 21, 2026 - 15:31 CISA

CVE Published

Aug 25, 2016 - 21:59 cve.org

HIGH 7.8

DescriptionCVE.org

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.

AnalysisAI

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. Rated high severity (CVSS 7.8), this vulnerability is no authentication required, low attack complexity. Actively exploited in the wild (cisa kev) and public exploit code available.

Technical ContextAI

This vulnerability is classified as Out-of-bounds Write (CWE-787), which allows attackers to write data beyond allocated buffer boundaries leading to code execution or crashes. 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. Affected products include: Apple Iphone Os. Version information: before 9.3.5.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Validate write boundaries, use memory-safe languages, enable compiler protections (ASLR, stack canaries).