diff --git a/.github/workflows/wheels-dependencies.sh b/.github/workflows/wheels-dependencies.sh
index 2605664eb..3ec314873 100755
--- a/.github/workflows/wheels-dependencies.sh
+++ b/.github/workflows/wheels-dependencies.sh
@@ -22,7 +22,7 @@ JPEGTURBO_VERSION=3.0.1
 OPENJPEG_VERSION=2.5.0
 XZ_VERSION=5.4.5
 TIFF_VERSION=4.6.0
-LCMS2_VERSION=2.15
+LCMS2_VERSION=2.16
 if [[ -n "$IS_MACOS" ]]; then
     GIFLIB_VERSION=5.1.4
 else
diff --git a/CHANGES.rst b/CHANGES.rst
index 5f58a2cad..d1fa91bfc 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -5,10 +5,13 @@ Changelog (Pillow)
 10.2.0 (unreleased)
 -------------------
 
+- Correct PDF palette size when saving #7555
+  [radarhere]
+
 - Fixed closing file pointer with olefile 0.47 #7594
   [radarhere]
 
-- Raise ValueError when TrueType font size is not greater than zero #7584
+- Raise ValueError when TrueType font size is not greater than zero #7584, #7587
   [akx, radarhere]
 
 - If absent, do not try to close fp when closing image #7557
diff --git a/docs/installation.rst b/docs/installation.rst
index aa78a7a00..fbcfbb907 100644
--- a/docs/installation.rst
+++ b/docs/installation.rst
@@ -175,7 +175,7 @@ Many of Pillow's features require external libraries:
 * **littlecms** provides color management
 
   * Pillow version 2.2.1 and below uses liblcms1, Pillow 2.3.0 and
-    above uses liblcms2. Tested with **1.19** and **2.7-2.15**.
+    above uses liblcms2. Tested with **1.19** and **2.7-2.16**.
 
 * **libwebp** provides the WebP format.
 
diff --git a/src/PIL/ImageFont.py b/src/PIL/ImageFont.py
index 0331a5c45..18de10375 100644
--- a/src/PIL/ImageFont.py
+++ b/src/PIL/ImageFont.py
@@ -188,6 +188,10 @@ class FreeTypeFont:
     def __init__(self, font=None, size=10, index=0, encoding="", layout_engine=None):
         # FIXME: use service provider instead
 
+        if size <= 0:
+            msg = "font size must be greater than 0"
+            raise ValueError(msg)
+
         self.path = font
         self.size = size
         self.index = index
@@ -791,10 +795,6 @@ def truetype(font=None, size=10, index=0, encoding="", layout_engine=None):
     :exception ValueError: If the font size is not greater than zero.
     """
 
-    if size <= 0:
-        msg = "font size must be greater than 0"
-        raise ValueError(msg)
-
     def freetype(font):
         return FreeTypeFont(font, size, index, encoding, layout_engine)
 
diff --git a/src/PIL/ImageStat.py b/src/PIL/ImageStat.py
index 12747d546..ab5d90cb7 100644
--- a/src/PIL/ImageStat.py
+++ b/src/PIL/ImageStat.py
@@ -21,9 +21,7 @@
 # See the README file for information on usage and redistribution.
 #
 
-import functools
 import math
-import operator
 
 
 class Stat:
@@ -65,10 +63,7 @@ class Stat:
 
     def _getcount(self):
         """Get total number of pixels in each layer"""
-        return [
-            functools.reduce(operator.add, self.h[i : i + 256])
-            for i in range(0, len(self.h), 256)
-        ]
+        return [sum(self.h[i : i + 256]) for i in range(0, len(self.h), 256)]
 
     def _getsum(self):
         """Get sum of all pixels in each layer"""
diff --git a/src/PIL/PdfImagePlugin.py b/src/PIL/PdfImagePlugin.py
index 09fc0c7e6..b6bb60911 100644
--- a/src/PIL/PdfImagePlugin.py
+++ b/src/PIL/PdfImagePlugin.py
@@ -96,7 +96,7 @@ def _write_image(im, filename, existing_pdf, image_refs):
         dict_obj["ColorSpace"] = [
             PdfParser.PdfName("Indexed"),
             PdfParser.PdfName("DeviceRGB"),
-            255,
+            len(palette) // 3 - 1,
             PdfParser.PdfBinary(palette),
         ]
         procset = "ImageI"  # indexed color
diff --git a/winbuild/build_prepare.py b/winbuild/build_prepare.py
index c5c9441d4..f7e145fb9 100644
--- a/winbuild/build_prepare.py
+++ b/winbuild/build_prepare.py
@@ -279,10 +279,10 @@ DEPS = {
         "libs": [r"objs\{msbuild_arch}\Release Static\freetype.lib"],
     },
     "lcms2": {
-        "url": SF_PROJECTS + "/lcms/files/lcms/2.15/lcms2-2.15.tar.gz/download",
-        "filename": "lcms2-2.15.tar.gz",
-        "dir": "lcms2-2.15",
-        "license": "COPYING",
+        "url": SF_PROJECTS + "/lcms/files/lcms/2.16/lcms2-2.16.tar.gz/download",
+        "filename": "lcms2-2.16.tar.gz",
+        "dir": "lcms2-2.16",
+        "license": "LICENSE",
         "patch": {
             r"Projects\VC2022\lcms2_static\lcms2_static.vcxproj": {
                 # default is /MD for x86 and /MT for x64, we need /MD always