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CVE-2016-4688 Apple CVE debrief

CVE-2016-4688 is a high-severity Apple FontParser vulnerability tied to crafted fonts. According to the source corpus, it can allow remote code execution or cause an application crash/denial of service on affected Apple operating system versions. The issue was publicly disclosed on 2017-02-20 and is rated CVSS 8.8 (HIGH).

Vendor
Apple
Product
CVE-2016-4688
CVSS
HIGH 8.8
CISA KEV
Not listed in stored evidence
Original CVE published
2017-02-20
Original CVE updated
2026-05-13
Advisory published
2017-02-20
Advisory updated
2026-05-13

Who should care

Apple device administrators, endpoint and mobile device management teams, security operations teams, and users who may open or process untrusted font content on affected iOS, macOS, tvOS, or watchOS versions.

Technical summary

The source corpus identifies a buffer overflow in Apple's FontParser component (CWE-119). NVD lists the attack vector as network-based with low attack complexity, no privileges required, and user interaction required (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). The vulnerability affects iOS before 10.1, macOS before 10.12.1, tvOS before 10.0.1, and watchOS versions listed in the corpus as before 3.1 and/or before 3.1.3. The impact described is arbitrary code execution or denial of service through a crafted font.

Defensive priority

High. The combination of remote code execution potential, low complexity, and user interaction makes this a priority patch for systems that ingest untrusted content or run exposed Apple OS versions.

Recommended defensive actions

  • Update affected Apple devices to vendor-fixed versions referenced by the Apple advisories and NVD.
  • Prioritize remediation for systems that regularly process untrusted documents, web content, or font files.
  • Inventory iOS, macOS, tvOS, and watchOS versions to confirm none remain below the affected thresholds.
  • Use centralized device management to verify compliance across fleets and flag lagging devices for immediate update.
  • Review the linked Apple security advisories and NVD record for product-specific remediation guidance.

Evidence notes

Based only on the supplied corpus: the CVE description, NVD metadata, and Apple vendor advisory references. NVD lists CWE-119 and CVSS 8.8 (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). The corpus includes Apple vendor advisories (HT207269, HT207270, HT207271, HT207275, HT207487) plus NVD and CVE.org records. No exploit code, proof-of-concept, or campaign attribution is present in the supplied data.

Official resources

Publicly disclosed on 2017-02-20 per the supplied CVE publication timestamp.