diff --git a/thirdparty/README.md b/thirdparty/README.md
index 635babbfc60..394d6098b01 100644
--- a/thirdparty/README.md
+++ b/thirdparty/README.md
@@ -262,6 +262,7 @@ File extracted from upstream release tarball `mbedtls-2.8.0-apache.tgz`:
 - All `*.c` from `library/` to `thirdparty/mbedtls/library/`
 - In file `thirdparty/mbedtls/library/net_sockets.c` mbedTLS overrides the `_WIN32_WINNT` define.
   Be sure to check the Godot addition to only redfine it when undefined or `< 0x0501` (PRed upstream).
+- Applied the patch in `thirdparty/mbedtls/1453.diff` (PR 1453). Soon to be merged upstream. Check it out at next update.
 
 ## minizip
 
diff --git a/thirdparty/mbedtls/1453.diff b/thirdparty/mbedtls/1453.diff
new file mode 100644
index 00000000000..acc3654cd47
--- /dev/null
+++ b/thirdparty/mbedtls/1453.diff
@@ -0,0 +1,120 @@
+diff --git a/thirdparty/mbedtls/library/entropy_poll.c b/thirdparty/mbedtls/library/entropy_poll.c
+index 67900c46c8..cefe882d2a 100644
+--- a/thirdparty/mbedtls/library/entropy_poll.c
++++ b/thirdparty/mbedtls/library/entropy_poll.c
+@@ -54,28 +54,43 @@
+ #define _WIN32_WINNT 0x0400
+ #endif
+ #include <windows.h>
+-#include <wincrypt.h>
++#include <bcrypt.h>
++#if defined(_MSC_VER) && _MSC_VER <= 1600
++/* Visual Studio 2010 and earlier issue a warning when both <stdint.h> and
++ * <intsafe.h> are included, as they redefine a number of <TYPE>_MAX constants.
++ * These constants are guaranteed to be the same, though, so we suppress the
++ * warning when including intsafe.h.
++ */
++#pragma warning( push )
++#pragma warning( disable : 4005 )
++#endif
++#include <intsafe.h>
++#if defined(_MSC_VER) && _MSC_VER <= 1600
++#pragma warning( pop )
++#endif
+ 
+ int mbedtls_platform_entropy_poll( void *data, unsigned char *output, size_t len,
+                            size_t *olen )
+ {
+-    HCRYPTPROV provider;
++    ULONG len_as_ulong = 0;
+     ((void) data);
+     *olen = 0;
+ 
+-    if( CryptAcquireContext( &provider, NULL, NULL,
+-                              PROV_RSA_FULL, CRYPT_VERIFYCONTEXT ) == FALSE )
++    /*
++     * BCryptGenRandom takes ULONG for size, which is smaller than size_t on
++     * 64-bit Windows platforms. Ensure len's value can be safely converted into
++     * a ULONG.
++     */
++    if ( FAILED( SizeTToULong( len, &len_as_ulong ) ) )
+     {
+         return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
+     }
+ 
+-    if( CryptGenRandom( provider, (DWORD) len, output ) == FALSE )
++    if ( !BCRYPT_SUCCESS( BCryptGenRandom( NULL, output, len_as_ulong, BCRYPT_USE_SYSTEM_PREFERRED_RNG ) ) )
+     {
+-        CryptReleaseContext( provider, 0 );
+         return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
+     }
+ 
+-    CryptReleaseContext( provider, 0 );
+     *olen = len;
+ 
+     return( 0 );
+diff --git a/thirdparty/mbedtls/library/x509_crt.c b/thirdparty/mbedtls/library/x509_crt.c
+index afff4e18bf..7960fa1a1a 100644
+--- a/thirdparty/mbedtls/library/x509_crt.c
++++ b/thirdparty/mbedtls/library/x509_crt.c
+@@ -64,6 +64,19 @@
+ 
+ #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
+ #include <windows.h>
++#if defined(_MSC_VER) && _MSC_VER <= 1600
++/* Visual Studio 2010 and earlier issue a warning when both <stdint.h> and
++ * <intsafe.h> are included, as they redefine a number of <TYPE>_MAX constants.
++ * These constants are guaranteed to be the same, though, so we suppress the
++ * warning when including intsafe.h.
++ */
++#pragma warning( push )
++#pragma warning( disable : 4005 )
++#endif
++#include <intsafe.h>
++#if defined(_MSC_VER) && _MSC_VER <= 1600
++#pragma warning( pop )
++#endif
+ #else
+ #include <time.h>
+ #endif
+@@ -1130,6 +1143,7 @@ int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
+     char filename[MAX_PATH];
+     char *p;
+     size_t len = strlen( path );
++    int lengthAsInt = 0;
+ 
+     WIN32_FIND_DATAW file_data;
+     HANDLE hFind;
+@@ -1144,7 +1158,18 @@ int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
+     p = filename + len;
+     filename[len++] = '*';
+ 
+-    w_ret = MultiByteToWideChar( CP_ACP, 0, filename, (int)len, szDir,
++    if ( FAILED ( SizeTToInt( len, &lengthAsInt ) ) )
++        return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
++
++    /*
++     * Note this function uses the code page CP_ACP, and assumes the incoming
++     * string is encoded in ANSI, before translating it into Unicode. If the
++     * incoming string were changed to be UTF-8, then the length check needs to
++     * change to check the number of characters, not the number of bytes, in the
++     * incoming string are less than MAX_PATH to avoid a buffer overrun with
++     * MultiByteToWideChar().
++     */
++    w_ret = MultiByteToWideChar( CP_ACP, 0, filename, lengthAsInt, szDir,
+                                  MAX_PATH - 3 );
+     if( w_ret == 0 )
+         return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
+@@ -1161,8 +1186,11 @@ int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
+         if( file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
+             continue;
+ 
++        if ( FAILED( SizeTToInt( wcslen( file_data.cFileName ), &lengthAsInt ) ) )
++            return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
++
+         w_ret = WideCharToMultiByte( CP_ACP, 0, file_data.cFileName,
+-                                     lstrlenW( file_data.cFileName ),
++                                     lengthAsInt,
+                                      p, (int) len - 1,
+                                      NULL, NULL );
+         if( w_ret == 0 )
diff --git a/thirdparty/mbedtls/library/entropy_poll.c b/thirdparty/mbedtls/library/entropy_poll.c
index a116e605d2f..ed350735d06 100644
--- a/thirdparty/mbedtls/library/entropy_poll.c
+++ b/thirdparty/mbedtls/library/entropy_poll.c
@@ -54,28 +54,43 @@
 #define _WIN32_WINNT 0x0400
 #endif
 #include <windows.h>
-#include <wincrypt.h>
+#include <bcrypt.h>
+#if defined(_MSC_VER) && _MSC_VER <= 1600
+/* Visual Studio 2010 and earlier issue a warning when both <stdint.h> and
+ * <intsafe.h> are included, as they redefine a number of <TYPE>_MAX constants.
+ * These constants are guaranteed to be the same, though, so we suppress the
+ * warning when including intsafe.h.
+ */
+#pragma warning( push )
+#pragma warning( disable : 4005 )
+#endif
+#include <intsafe.h>
+#if defined(_MSC_VER) && _MSC_VER <= 1600
+#pragma warning( pop )
+#endif
 
 int mbedtls_platform_entropy_poll( void *data, unsigned char *output, size_t len,
                            size_t *olen )
 {
-    HCRYPTPROV provider;
+    ULONG len_as_ulong = 0;
     ((void) data);
     *olen = 0;
 
-    if( CryptAcquireContext( &provider, NULL, NULL,
-                              PROV_RSA_FULL, CRYPT_VERIFYCONTEXT ) == FALSE )
+    /*
+     * BCryptGenRandom takes ULONG for size, which is smaller than size_t on
+     * 64-bit Windows platforms. Ensure len's value can be safely converted into
+     * a ULONG.
+     */
+    if ( FAILED( SizeTToULong( len, &len_as_ulong ) ) )
     {
         return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
     }
 
-    if( CryptGenRandom( provider, (DWORD) len, output ) == FALSE )
+    if ( !BCRYPT_SUCCESS( BCryptGenRandom( NULL, output, len_as_ulong, BCRYPT_USE_SYSTEM_PREFERRED_RNG ) ) )
     {
-        CryptReleaseContext( provider, 0 );
         return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
     }
 
-    CryptReleaseContext( provider, 0 );
     *olen = len;
 
     return( 0 );
diff --git a/thirdparty/mbedtls/library/x509_crt.c b/thirdparty/mbedtls/library/x509_crt.c
index daa316367b5..2a5dbb87833 100644
--- a/thirdparty/mbedtls/library/x509_crt.c
+++ b/thirdparty/mbedtls/library/x509_crt.c
@@ -62,6 +62,19 @@
 
 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
 #include <windows.h>
+#if defined(_MSC_VER) && _MSC_VER <= 1600
+/* Visual Studio 2010 and earlier issue a warning when both <stdint.h> and
+ * <intsafe.h> are included, as they redefine a number of <TYPE>_MAX constants.
+ * These constants are guaranteed to be the same, though, so we suppress the
+ * warning when including intsafe.h.
+ */
+#pragma warning( push )
+#pragma warning( disable : 4005 )
+#endif
+#include <intsafe.h>
+#if defined(_MSC_VER) && _MSC_VER <= 1600
+#pragma warning( pop )
+#endif
 #else
 #include <time.h>
 #endif
@@ -1114,6 +1127,7 @@ int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
     char filename[MAX_PATH];
     char *p;
     size_t len = strlen( path );
+    int lengthAsInt = 0;
 
     WIN32_FIND_DATAW file_data;
     HANDLE hFind;
@@ -1128,7 +1142,18 @@ int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
     p = filename + len;
     filename[len++] = '*';
 
-    w_ret = MultiByteToWideChar( CP_ACP, 0, filename, (int)len, szDir,
+    if ( FAILED ( SizeTToInt( len, &lengthAsInt ) ) )
+        return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
+
+    /*
+     * Note this function uses the code page CP_ACP, and assumes the incoming
+     * string is encoded in ANSI, before translating it into Unicode. If the
+     * incoming string were changed to be UTF-8, then the length check needs to
+     * change to check the number of characters, not the number of bytes, in the
+     * incoming string are less than MAX_PATH to avoid a buffer overrun with
+     * MultiByteToWideChar().
+     */
+    w_ret = MultiByteToWideChar( CP_ACP, 0, filename, lengthAsInt, szDir,
                                  MAX_PATH - 3 );
     if( w_ret == 0 )
         return( MBEDTLS_ERR_X509_BAD_INPUT_DATA );
@@ -1145,8 +1170,11 @@ int mbedtls_x509_crt_parse_path( mbedtls_x509_crt *chain, const char *path )
         if( file_data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY )
             continue;
 
+        if ( FAILED( SizeTToInt( wcslen( file_data.cFileName ), &lengthAsInt ) ) )
+            return( MBEDTLS_ERR_X509_FILE_IO_ERROR );
+
         w_ret = WideCharToMultiByte( CP_ACP, 0, file_data.cFileName,
-                                     lstrlenW( file_data.cFileName ),
+                                     lengthAsInt,
                                      p, (int) len - 1,
                                      NULL, NULL );
         if( w_ret == 0 )