diff --git a/releases.json b/releases.json
index 51b7df00d..27580e0b7 100644
--- a/releases.json
+++ b/releases.json
@@ -1541,6 +1541,7 @@
       "libturbojpeg"
     ],
     "versions": [
+      "3.0.3-1",
       "3.0.2-1",
       "3.0.1-1",
       "3.0.0-5",
diff --git a/subprojects/libjpeg-turbo.wrap b/subprojects/libjpeg-turbo.wrap
index 9d545ba8f..45bbcb2d7 100644
--- a/subprojects/libjpeg-turbo.wrap
+++ b/subprojects/libjpeg-turbo.wrap
@@ -1,8 +1,8 @@
 [wrap-file]
-directory = libjpeg-turbo-3.0.2
-source_url = https://github.com/libjpeg-turbo/libjpeg-turbo/releases/download/3.0.2/libjpeg-turbo-3.0.2.tar.gz
-source_filename = libjpeg-turbo-3.0.2.tar.gz
-source_hash = c2ce515a78d91b09023773ef2770d6b0df77d674e144de80d63e0389b3a15ca6
+directory = libjpeg-turbo-3.0.3
+source_url = https://github.com/libjpeg-turbo/libjpeg-turbo/releases/download/3.0.3/libjpeg-turbo-3.0.3.tar.gz
+source_filename = libjpeg-turbo-3.0.3.tar.gz
+source_hash = 343e789069fc7afbcdfe44dbba7dbbf45afa98a15150e079a38e60e44578865d
 patch_directory = libjpeg-turbo
 
 [provide]
diff --git a/subprojects/packagefiles/libjpeg-turbo/meson.build b/subprojects/packagefiles/libjpeg-turbo/meson.build
index 2ee2dce09..7331f7b6f 100644
--- a/subprojects/packagefiles/libjpeg-turbo/meson.build
+++ b/subprojects/packagefiles/libjpeg-turbo/meson.build
@@ -1,5 +1,5 @@
 project('libjpeg-turbo', 'c',
-  version : '3.0.2',
+  version : '3.0.3',
   license : 'bsd-like',
   meson_version : '>= 0.64.0')
 
@@ -13,7 +13,7 @@ host_cpu = host_machine.cpu_family()
 cdata = configuration_data()
 cdata.set('CMAKE_PROJECT_NAME', meson.project_name())
 cdata.set('VERSION', meson.project_version())
-cdata.set('COPYRIGHT_YEAR', '1991-2023')
+cdata.set('COPYRIGHT_YEAR', '1991-2024')
 
 jpeg_lib_version = 80
 so_major = jpeg_lib_version / 10
@@ -77,13 +77,13 @@ if meson.can_run_host_binaries()
   code = '''
       #include <stdio.h>
       #include <stdlib.h>
-      int is_shifting_signed (long arg) {
+      static int is_shifting_signed (long arg) {
         long res = arg >> 4;
         if (res == -0x7F7E80CL)
           return 1; /* right shift is signed */
         /* see if unsigned-shift hack will fix it. */
         /* we can't just test exact value since it depends on width of long... */
-        res |= (~0L) << (32-4);
+        res |= 0xFFFFFFFFL << (32-4);
         if (res == -0x7F7E80CL)
           return 0; /* right shift is unsigned */
         printf(\"Right shift isn't acting as I expect it to.\\\\n\");
diff --git a/subprojects/packagefiles/libjpeg-turbo/simd/meson.build b/subprojects/packagefiles/libjpeg-turbo/simd/meson.build
index b12c31aa8..7116fa827 100644
--- a/subprojects/packagefiles/libjpeg-turbo/simd/meson.build
+++ b/subprojects/packagefiles/libjpeg-turbo/simd/meson.build
@@ -42,6 +42,17 @@ if host_cpu in ['x86', 'x86_64']
   if have_simd
     add_project_arguments('-DPIC', language: 'nasm')
     x64 = host_cpu == 'x86_64'
+    # simulate upstream's "is ELF" check by excluding non-ELF OSes
+    if x64 and host_machine.system() not in ['cygwin', 'darwin', 'windows']
+      if cc.compiles('''
+        #if (__CET__ & 3) == 0
+        #error \"CET not enabled\"
+        #endif
+        int main(void) { return 0; }
+      ''')
+        add_project_arguments('-D__CET__', language: 'nasm')
+      endif
+    endif
     dir = x64 ? 'x86_64' : 'i386'
     simd_src = x64 ? simd_src_x86_64 : simd_src_i386
     simd = static_library('simd', dir / 'jsimd.c',