Executive brief
A security vulnerability in Apple operating systems could allow a malicious app to bypass code signing protections. Code signing is a critical security feature that ensures apps are from trusted sources and have not been tampered with. If exploited, an unauthorized application could run on a device with elevated privileges or perform actions it is not permitted to do.
Technical details
A validation issue existed in the code signing enforcement mechanism across multiple Apple operating systems. The vulnerability was rooted in insufficient input sanitization, which could be exploited by a maliciously crafted application to bypass signature verification. By successfully bypassing these checks, an attacker could execute unsigned or improperly signed code on the target system. Apple addressed this issue in the 26.6 updates for iOS, iPadOS, macOS Tahoe, tvOS, visionOS, and watchOS by implementing improved input sanitization.
Affected products
- Apple iOS and iPadOS before 26.6
- Apple macOS Tahoe before 26.6
- Apple tvOS before 26.6
- Apple visionOS before 26.6
- Apple watchOS before 26.6
Timeline
- 2026-07-27: disclosed
- 2026-07-27: patched