diff --git a/ports/cserialport/portfile.cmake b/ports/cserialport/portfile.cmake
index d6fa979127..2224fffcf4 100644
--- a/ports/cserialport/portfile.cmake
+++ b/ports/cserialport/portfile.cmake
@@ -1,8 +1,9 @@
 vcpkg_from_github(
     OUT_SOURCE_PATH SOURCE_PATH
     REPO itas109/CSerialPort
-    REF v4.1.1
-    SHA512 4e0b6d5d07ac9f213762a8bf6a90a109ec134b04a8645dc5fc0b89c69a798c857924ee37f13f421b421148bc39bf1ed4f37361e5d1d9f7f51e0faf01757b3927
+    REF v4.2.1
+    SHA512 a5d30ab1a970a1989b9295d37285a5043946164910b9ed455661b96e0b42a9d9c71d7ea9d23bbe3dc5d1c2f33ff0265320e0bb3199243146ba2eeb263757335f
+    HEAD_REF master
 )
 
 vcpkg_cmake_configure(
diff --git a/ports/cserialport/vcpkg.json b/ports/cserialport/vcpkg.json
index 2be7ba1971..65360e98af 100644
--- a/ports/cserialport/vcpkg.json
+++ b/ports/cserialport/vcpkg.json
@@ -1,7 +1,7 @@
 {
   "name": "cserialport",
-  "version": "4.1.1",
-  "description": "c++ lightweight cross-platform serial port library",
+  "version": "4.2.1",
+  "description": "C++ lightweight cross-platform serial port library, also support C#, Java, Python, Node.js etc.",
   "homepage": "https://github.com/itas109/CSerialPort",
   "license": "LGPL-3.0-only",
   "supports": "!uwp",
diff --git a/versions/baseline.json b/versions/baseline.json
index 04563be4f7..a6eaa3c87e 100644
--- a/versions/baseline.json
+++ b/versions/baseline.json
@@ -1757,7 +1757,7 @@
       "port-version": 0
     },
     "cserialport": {
-      "baseline": "4.1.1",
+      "baseline": "4.2.1",
       "port-version": 0
     },
     "cspice": {
diff --git a/versions/c-/cserialport.json b/versions/c-/cserialport.json
index 32e935a910..572f12a1c3 100644
--- a/versions/c-/cserialport.json
+++ b/versions/c-/cserialport.json
@@ -1,5 +1,10 @@
 {
   "versions": [
+    {
+      "git-tree": "d77a5c24de68d33668252720bd2450ff86b1dc94",
+      "version": "4.2.1",
+      "port-version": 0
+    },
     {
       "git-tree": "40b712199f0d2fdacdb68dae7bbf03a0bcab7918",
       "version": "4.1.1",