diff --git a/CMakeLists.txt b/CMakeLists.txt
index d57e18275..8dcf6793d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -103,6 +103,9 @@ if(HAVE_X86_SSE_MATH)
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -msse2 -mfpmath=sse")
 endif()
 
+# On i386 Linux we can fix unaligned SSE malloc (see GitHub issue #4432)
+include(FindUnalignedMalloc)
+
 if(WIN32)
     # Add additional paths. Look in the MinGW path first, then in the Gtkmm path.
     # If you wish to build some dependent libraries, you have to install them in MinGW to use them:
diff --git a/cmake/modules/FindUnalignedMalloc.cmake b/cmake/modules/FindUnalignedMalloc.cmake
new file mode 100644
index 000000000..4ddfb2afc
--- /dev/null
+++ b/cmake/modules/FindUnalignedMalloc.cmake
@@ -0,0 +1,49 @@
+# This file is part of RawTherapee.
+#
+# Copyright (C) 2018 Flössie <floessie.mail@gmail.com>
+#
+# RawTherapee is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# RawTherapee is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with RawTherapee.  If not, see <http://www.gnu.org/licenses/>.
+
+include(CheckCXXSourceCompiles)
+
+set(CMAKE_REQUIRED_QUIET_COPY "${CMAKE_REQUIRED_QUIET}")
+set(CMAKE_REQUIRED_QUIET ON)
+
+set(TEST_SOURCE
+"
+#include <cstddef>
+#include <type_traits>
+
+int main()
+{
+#if defined(__SSE2__) && (defined(__i386) || defined(_M_IX86)) && defined(__linux)
+    static_assert(std::alignment_of<std::max_align_t>::value >= 16, \"Unaligned heap objects possible\");
+#endif
+
+    return 0;
+}
+")
+
+CHECK_CXX_SOURCE_COMPILES("${TEST_SOURCE}" HAVE_ALIGNED_MALLOC)
+
+if(NOT HAVE_ALIGNED_MALLOC)
+    set(HAVE_UNALIGNED_MALLOC 1)
+else()
+    unset(HAVE_ALIGNED_MALLOC)
+endif()
+
+unset(TEST_SOURCE)
+
+set(CMAKE_REQUIRED_QUIET "${CMAKE_REQUIRED_QUIET_COPY}")
+unset(CMAKE_REQUIRED_QUIET_COPY)
diff --git a/rtgui/CMakeLists.txt b/rtgui/CMakeLists.txt
index 540b4d267..c39ed004c 100644
--- a/rtgui/CMakeLists.txt
+++ b/rtgui/CMakeLists.txt
@@ -1,5 +1,6 @@
 # Common source files for both CLI and non-CLI execautables
 set(CLISOURCEFILES
+    alignedmalloc.cc
     edit.cc
     main-cli.cc
     multilangmgr.cc
@@ -11,6 +12,7 @@ set(CLISOURCEFILES
 
 set(NONCLISOURCEFILES
     adjuster.cc
+    alignedmalloc.cc
     batchqueue.cc
     batchqueuebuttonset.cc
     batchqueueentry.cc
diff --git a/rtgui/alignedmalloc.cc b/rtgui/alignedmalloc.cc
new file mode 100644
index 000000000..91fe15a85
--- /dev/null
+++ b/rtgui/alignedmalloc.cc
@@ -0,0 +1,31 @@
+/*
+ *  This file is part of RawTherapee.
+ *
+ *  Copyright (C) 2018 Flössie <floessie.mail@gmail.com>
+ *
+ *  RawTherapee is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  RawTherapee is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with RawTherapee.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#ifdef HAVE_UNALIGNED_MALLOC
+
+#include <malloc.h>
+
+void* malloc(size_t size)
+{
+    return memalign(16, size);
+}
+
+#endif
diff --git a/rtgui/config.h.in b/rtgui/config.h.in
index fdf64b73c..2d1f41dbc 100644
--- a/rtgui/config.h.in
+++ b/rtgui/config.h.in
@@ -21,6 +21,7 @@
 #define __CONFIG_H__
 
 #cmakedefine BUILD_BUNDLE
+#cmakedefine HAVE_UNALIGNED_MALLOC
 #define DATA_SEARCH_PATH "${DATADIR}"
 #define DOC_SEARCH_PATH "${DOCDIR}"
 #define CREDITS_SEARCH_PATH "${CREDITSDIR}"