Out-of-bounds write in Apple FontParser
CVE-2025-43400 is an out-of-bounds write vulnerability in Apple’s FontParser component affecting multiple Apple operating systems. According to the provided content, the flaw is triggered when the system or an application processes a maliciously crafted font. Apple states the issue was addressed through improved bounds checking. The vulnerable condition can lead to memory corruption during font parsing, causing unexpected application termination or corruption of process memory. Affected platforms mentioned in the content include iOS 18.7.1 and earlier, iPadOS 18.7.1 and earlier, iOS 26.0.1 and earlier, iPadOS 26.0.1 and earlier, macOS Sequoia 15.7.1 and earlier, macOS Sonoma 14.8.1 and earlier, macOS Tahoe 26.0.1 and earlier, tvOS 26.1 and earlier, visionOS 26.0.1 and earlier, and watchOS 26.1 and earlier.
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Exploits
No valid public exploits. Mallory filtered out 1 candidate as fakes, detection scripts, or README-only repos.
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Recent activity
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A critical vulnerability affecting multiple Apple operating systems, details not specified in the content.
An out-of-bounds write vulnerability in Apple’s FontParser component that can be triggered by processing a maliciously crafted font, potentially leading to denial-of-service, memory corruption, or arbitrary code execution.
A critical out-of-bounds write vulnerability in Apple's FontParser component affecting macOS, iOS, iPadOS, and related products. Exploitation could allow arbitrary code execution via a maliciously crafted font file.
An out-of-bounds write vulnerability in Apple software where processing a maliciously crafted font may cause unexpected app termination or corrupt process memory.
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Every observed campaign linking this CVE to a named adversary.
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Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.