CVE-2025-43438

Overview

Advisory: Apple Security Advisory

Impact:

Description: Processing maliciously crafted web content may lead to an unexpected Safari crash

Researchers: rheza (@ginggilBesel), shandikri working with Trend Micro Zero Day Initiative

Attribute Value
CVE CVE-2025-43438
Bugzilla 297662
Component JSC
Bug Class UAF
Severity medium
Commit 045fd8ec92379f84…
Advisory Apple Advisory

Root Cause Analysis

A use-after-free issue was addressed with improved memory management.

Files Changed

Source Files

  • Source/JavaScriptCore/bytecode/SpeculatedType.cpp
  • Source/JavaScriptCore/bytecode/SpeculatedType.h
  • Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp
  • Source/JavaScriptCore/dfg/DFGUseKind.h
  • Source/JavaScriptCore/ftl/FTLLowerDFGToB3.cpp
  • Source/JavaScriptCore/runtime/JSType.h

Test Files

  • JSTests/stress/map-set-iterator-speculated-types.js