The Apple Security Update Review for September 2026
Apple's September 2026 updates patch 45+ flaws, including a 9.8 Screen Sharing authentication bypass (CVE-2026-65400) already listed in CISA's KEV.
ZDI's review of Apple's September 2026 security updates catalogs dozens of CVEs across macOS, iOS, iPadOS, watchOS and other platforms. CVE-2026-65400 (CVSS 9.8) lets a network attacker authenticate to Screen Sharing Server without valid credentials and is flagged as KEV, while CVE-2026-65414 (CVSS 9.8) enables remote code execution via Bluetooth. The set also includes 8.8-rated memory corruption flaws in WebKit, WebRTC, CUPS, ImageIO and the kernel, plus sandbox escapes, privilege escalations to root, and arbitrary code execution via crafted files.
Vulnerability Spotlight: Apple Safari SVG marker element baseVal remote code execution vulnerability
Apple Updates Everything, (Mon, Sep 14th)
Apple patched a record 261 vulnerabilities across iOS 27, macOS Golden Gate 27, watchOS 27, and other platforms, with none flagged as exploited.
Apple's annual OS update shipped iOS/iPadOS 27, macOS Golden Gate 27, tvOS 27, watchOS 27, and visionOS 27 plus bug-fix releases for the 26 and 15 branches, fixing a record 261 vulnerabilities. Notable issues include multiple kernel flaws allowing root privilege escalation (CVE-2026-43689, CVE-2026-43691, CVE-2026-43698, CVE-2026-43786), remote code execution in CUPS (CVE-2026-43692), kernel memory corruption via malicious NFS servers (CVE-2026-43686, CVE-2026-43687), and WebKit memory corruption from crafted web content (CVE-2026-43715). No vulnerabilities are labeled as actively exploited, and Apple does not assign per-CVE severities. Users report iOS 26.7 being downloaded when iOS 27 is intended, and tools like Little Snitch and BlockBlock need updates before upgrading to macOS 27.
ZDI-26-610: Apple Safari JavaScriptCore B3 ReduceStrength Phase Use-After-Free Remote Code Execution Vulnerability
ZDI details a use-after-free in Apple Safari's JavaScriptCore (CVE-2026-64715) that allows remote code execution after a user visits a malicious page.
The Zero Day Initiative published advisory ZDI-26-610 for a use-after-free in the B3 ReduceStrength phase of Apple Safari's JavaScriptCore. Successful exploitation allows remote attackers to execute arbitrary code, but user interaction is required, such as visiting a malicious page or opening a malicious file. ZDI rates the vulnerability 8.8 on CVSS and assigned CVE-2026-64715. The advisory does not report exploitation in the wild.