How severe is CVE-2016-4656?

CVE-2016-4656 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2016-4656 being actively exploited?

Yes. CVE-2016-4656 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-05-24, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2016-4656?

CVE-2016-4656 affects Apple Iphone Os. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-4656?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2016-4656 have an EU (EUVD) identifier?

Yes. CVE-2016-4656 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2016-5642. It is also flagged as exploited in the EUVD (since 2022-05-24).

When was CVE-2016-4656 published?

CVE-2016-4656 was published on 2016-08-25 and last updated on 2026-06-17.

CVE-2016-4656

CVE-2016-4656 is a high-severity vulnerability in Apple Iphone Os with a CVSS 3.x base score of 7.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-05-24). The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 9.3
EPSS exploit prediction: 24% (98th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-05-24)
EU (EUVD) id: EUVD-2016-5642
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-05-24)
Weakness: CWE-787
Affected product: Apple Iphone Os
Published: 2016-08-25
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2016-4656?: 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.
How severe is CVE-2016-4656?: CVE-2016-4656 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2016-4656 being actively exploited?: Yes. CVE-2016-4656 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-05-24, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2016-4656?: CVE-2016-4656 affects Apple Iphone Os. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-4656?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2016-4656 have an EU (EUVD) identifier?: Yes. CVE-2016-4656 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2016-5642. It is also flagged as exploited in the EUVD (since 2022-05-24).
When was CVE-2016-4656 published?: CVE-2016-4656 was published on 2016-08-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*

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