WebKit Integer Overflow (CVE‑2021‑30663) Enables Remote Code Execution Across Apple iOS, macOS, tvOS, and Safari
What It Is — Apple’s WebKit engine in iOS, iPadOS, macOS, tvOS and Safari contains an integer‑overflow flaw that can be triggered by malicious web content, resulting in arbitrary code execution. The issue also affects any third‑party application that embeds WebKit for HTML rendering.
Exploitability — Publicly disclosed; proof‑of‑concept code exists and can be delivered via a crafted web page. CVSS v3.1 base score 8.8 (High).
Affected Products — Apple iOS 15+, iPadOS 15+, macOS 12+, tvOS 15+, Safari 15+ (and any non‑Apple product that ships with the vulnerable WebKit version).
Why It Matters for Trust & Control Assurance
- Continuous monitoring of third‑party component vulnerabilities is a core control‑area that underpins audit‑ready evidence across frameworks.
- Timely patching of WebKit demonstrates due‑diligence in the “Vulnerability Management” control objective, a signal of robust risk mitigation to enterprise buyers.
- Demonstrable evidence of remediation (e.g., patch‑level inventories) feeds directly into a defensible audit trail for compliance reviews.
Recommended Actions
- Deploy Apple’s security updates that remediate CVE‑2021‑30663 on all affected devices.
- Verify patch levels through automated inventory tools and record evidence of compliance.
- Integrate WebKit version checks into your continuous vulnerability‑management workflow.
Source: CISA KEV – CVE‑2021‑30663