diff --git a/.github/workflows/wheels-dependencies.sh b/.github/workflows/wheels-dependencies.sh
index 5c2da9b25..f0ffd87d4 100755
--- a/.github/workflows/wheels-dependencies.sh
+++ b/.github/workflows/wheels-dependencies.sh
@@ -18,7 +18,7 @@ ARCHIVE_SDIR=pillow-depends-main
 FREETYPE_VERSION=2.13.2
 HARFBUZZ_VERSION=8.3.0
 LIBPNG_VERSION=1.6.43
-JPEGTURBO_VERSION=3.0.1
+JPEGTURBO_VERSION=3.0.2
 OPENJPEG_VERSION=2.5.2
 XZ_VERSION=5.4.5
 TIFF_VERSION=4.6.0
@@ -29,7 +29,7 @@ else
     GIFLIB_VERSION=5.2.1
 fi
 if [[ -n "$IS_MACOS" ]] || [[ "$MB_ML_VER" != 2014 ]]; then
-    ZLIB_VERSION=1.3
+    ZLIB_VERSION=1.3.1
 else
     ZLIB_VERSION=1.2.8
 fi
diff --git a/CHANGES.rst b/CHANGES.rst
index 44dfa65f7..243c6b82a 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -5,6 +5,9 @@ Changelog (Pillow)
 10.3.0 (unreleased)
 -------------------
 
+- Fix shift-sign issue in Convert.c #7838
+  [r-barnes, radarhere]
+
 - Open 16-bit grayscale PNGs as I;16 #7849
   [radarhere]
 
diff --git a/src/libImaging/Convert.c b/src/libImaging/Convert.c
index 2654fd40d..5cc39cd00 100644
--- a/src/libImaging/Convert.c
+++ b/src/libImaging/Convert.c
@@ -510,7 +510,7 @@ rgbT2rgba(UINT8 *out, int xsize, int r, int g, int b) {
     UINT32 trns = ((r & 0xff) << 24) | ((g & 0xff) << 16) | ((b & 0xff) << 8) | 0xff;
     UINT32 repl = trns & 0xffffff00;
 #else
-    UINT32 trns = (0xff << 24) | ((b & 0xff) << 16) | ((g & 0xff) << 8) | (r & 0xff);
+    UINT32 trns = (0xffU << 24) | ((b & 0xff) << 16) | ((g & 0xff) << 8) | (r & 0xff);
     UINT32 repl = trns & 0x00ffffff;
 #endif
 
diff --git a/winbuild/build_prepare.py b/winbuild/build_prepare.py
index 0510a02d8..5e144d598 100644
--- a/winbuild/build_prepare.py
+++ b/winbuild/build_prepare.py
@@ -114,14 +114,14 @@ V = {
     "FREETYPE": "2.13.2",
     "FRIBIDI": "1.0.13",
     "HARFBUZZ": "8.3.0",
-    "JPEGTURBO": "3.0.1",
+    "JPEGTURBO": "3.0.2",
     "LCMS2": "2.16",
     "LIBPNG": "1.6.43",
     "LIBWEBP": "1.3.2",
     "OPENJPEG": "2.5.2",
     "TIFF": "4.6.0",
     "XZ": "5.4.5",
-    "ZLIB": "1.3",
+    "ZLIB": "1.3.1",
 }
 V["LIBPNG_DOTLESS"] = V["LIBPNG"].replace(".", "")
 V["LIBPNG_XY"] = "".join(V["LIBPNG"].split(".")[:2])