Threat Intelligence / CVE / CVE-2016-4656

CVE-2016-4656 — Apple Iphone Os

CISA KEV
CVSS v3.1 7.8 (HIGH) · EPSS 21.3% (higher than 97.3% of all scored CVEs) · Priority 9/10 · Published 2016-08-25

As of 2025-10-21, CVE-2016-4656 is a HIGH-severity vulnerability in Apple Iphone Os, CVSS v3.1 7.8, EPSS 21.3% (97.3th percentile). It is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-05-24), with a US federal remediation deadline of 2022-06-14. Threadlinqs Intelligence links 2 tracked threat campaigns to CVE-2016-4656, most recently “NSO Group Co-Founder Shalev Hulio Held Israeli Diplomatic Passport in Panama, Raising State-Ties Questions for Pegasus Spyware Vendor”.

Last updated: 2025-10-21

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.

The record classifies CVE-2016-4656 under weakness class CWE-787. Its CVSS v3 base vector states that the flaw requires local access to the host, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 3671 days ago.

Severity and exploitation probability

CVSS v3.1 base score
7.8 — HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS (FIRST)
21.3% probability of exploitation in the next 30 days, higher than 97.3% of all scored CVEs
CISA KEV
Listed since 2022-05-24, federal remediation deadline 2022-06-14
Threadlinqs priority
9/10 — CISA KEV-listed, which Threadlinqs floors at 9
Published
2016-08-25, last modified 2025-10-21

Is CVE-2016-4656 being exploited?

CISA added CVE-2016-4656 to the Known Exploited Vulnerabilities catalog on 2022-05-24, which means the agency holds evidence of exploitation in the wild; US federal civilian agencies had to remediate it by 2022-06-14 under BOD 22-01. Weaponised exploit code for CVE-2016-4656 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 42 in the Threadlinqs vulnerability feed.

Affected products and versions

How to fix CVE-2016-4656

Vendor advisory: http://lists.apple.com/archives/security-announce/2016/Aug/msg00000.html. Because CVE-2016-4656 is KEV-listed, US federal civilian agencies were required to apply the vendor fix, or stop using the product, by 2022-06-14. Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

Threat activity tracking CVE-2016-4656

2 tracked threats in the Threadlinqs corpus reference CVE-2016-4656, either in the campaign’s CVE list or as an indicator on the campaign record.

Sources

Enriched from CVE.org, NVD, FIRST EPSS, CISA KEV, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.

Vendor advisory and patch

Exploit and proof of concept

Vulnerability database entry

Other references

Full detection coverage & IOCs for threats exploiting CVE-2016-4656 are available via the Threadlinqs MCP server (Purple tier). View plans →

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