Index: llvm/lib/Object/WasmObjectFile.cpp
===================================================================
--- llvm/lib/Object/WasmObjectFile.cpp
+++ llvm/lib/Object/WasmObjectFile.cpp
@@ -218,7 +218,12 @@
   if (Section.Type == wasm::WASM_SEC_CUSTOM) {
     const uint8_t *NameStart = Ctx.Ptr;
     Section.Name = readString(Ctx);
-    Size -= Ctx.Ptr - NameStart;
+    const uint32_t NameLength = Ctx.Ptr - NameStart;
+    if (NameLength > Size)
+      return make_error<StringError>(
+          "Custom section name extends beyond section",
+          object_error::parse_failed);
+    Size -= NameLength;
   }
   Section.Content = ArrayRef<uint8_t>(Ctx.Ptr, Size);
   Ctx.Ptr += Size;
Index: llvm/test/Object/wasm-string-outside-section.test
===================================================================
--- /dev/null
+++ llvm/test/Object/wasm-string-outside-section.test
@@ -0,0 +1,3 @@
+RUN: not llvm-objdump -s %p/Inputs/WASM/string-outside-section.wasm 2>&1 | FileCheck %s
+
+CHECK: Custom section name extends beyond section