CVE-2025-43295: 
macOS vulnerability analysis and mitigation

CVE-2025-43295 is a denial-of-service vulnerability in Apple's libc component affecting iOS, iPadOS, and macOS. A local app may be able to cause a denial-of-service by triggering uncontrolled resource consumption due to insufficient input validation. The vulnerability was disclosed on September 15, 2025, and affects iOS/iPadOS prior to 18.7, macOS Sonoma prior to 14.8, macOS Sequoia prior to 15.7, and macOS Tahoe 26. It carries a CVSS v3.1 base score of 5.5 (Medium) (Apple iOS/iPadOS Advisory, Apple Sonoma Advisory).

The vulnerability is classified as CWE-400 (Uncontrolled Resource Consumption) and resides in Apple's libc library. Insufficient validation within libc allows a locally-executed application to exhaust system resources, leading to a denial-of-service condition. Exploitation requires user interaction (e.g., a user running a malicious app) and no special privileges, with the attack vector being local. The fix was implemented via improved input validation in the affected libc component. The vulnerability was discovered and reported by Nathaniel Oh (@calysteon) (Apple iOS/iPadOS Advisory, Apple Sequoia Advisory).

Successful exploitation causes a high availability impact, potentially rendering the affected device unresponsive or crashing the system. There is no confidentiality or integrity impact — the vulnerability is limited to availability. The scope is unchanged, meaning the impact is confined to the affected system without enabling lateral movement or data exfiltration (Apple Sonoma Advisory, Apple Tahoe Advisory).

There is no public proof-of-concept exploit and no evidence of in-the-wild exploitation as of the time of disclosure. The EPSS score is approximately 0.018%, indicating a very low probability of exploitation in the near term. The vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog. No threat actor attribution has been reported (Apple iOS/iPadOS Advisory).

Apple has released patches addressing this vulnerability across all affected platforms. Users should update to the following versions or later: iOS 18.7, iPadOS 18.7, macOS Sonoma 14.8, macOS Sequoia 15.7, or macOS Tahoe 26. As a supplementary measure, organizations should restrict installation of applications from untrusted sources and monitor system resource utilization for unusual patterns (Apple iOS/iPadOS Advisory, Apple Sonoma Advisory, Apple Sequoia Advisory, Apple Tahoe Advisory).