An out‑of‑bounds write in the font parsing component was addressed with improved bounds checking. The flaw can be triggered by processing a maliciously crafted font, leading to unexpected application termination or corruption of process memory. This weakness is categorized as CWE‑787, which can result in denial‑of‑service or, in some scenarios, give an attacker a foothold to execute code in the context of the affected application.

The vulnerability affects Apple operating systems including iOS 18.7.1 and iOS 26.0.1, iPadOS 18.7.1 and iPadOS 26.0.1, macOS Sequoia 15.7.1, macOS Sonoma 14.8.1, macOS Tahoe 26.0.1, tvOS 26.1, visionOS 26.0.1, and watchOS 26.1. Devices running these OS versions could be impacted by loading a malicious font file.

The CVSS score of 6.3 indicates a moderate severity, and the EPSS score is less than 1 %, implying a low probability of exploitation at this time. The vulnerability is not listed in the CISA KEV catalog. Exploitation likely requires local access to an application that processes fonts, making it a potential local privilege escalation or denial‑of‑service vector when a user opens a crafted font file.