diff --git a/common/rfb/CMsgReader.cxx b/common/rfb/CMsgReader.cxx
index 2b5b9fb..a928eb1 100644
--- a/common/rfb/CMsgReader.cxx
+++ b/common/rfb/CMsgReader.cxx
@@ -157,10 +157,10 @@
     vlog.error("cut text too long (%d bytes) - ignoring",len);
     return;
   }
-  CharArray ca(len+1);
-  ca.buf[len] = 0;
+  CharArray ca(len);
   is->readBytes(ca.buf, len);
-  handler->serverCutText(ca.buf, len);
+  CharArray filtered(convertLF(ca.buf, len));
+  handler->serverCutText(filtered.buf, strlen(filtered.buf));
 }
 
 void CMsgReader::readFence()
diff --git a/common/rfb/CMsgWriter.cxx b/common/rfb/CMsgWriter.cxx
index d357c97..fed0bd2 100644
--- a/common/rfb/CMsgWriter.cxx
+++ b/common/rfb/CMsgWriter.cxx
@@ -181,6 +181,9 @@
 
 void CMsgWriter::writeClientCutText(const char* str, rdr::U32 len)
 {
+  if (memchr(str, '\r', len) != NULL)
+    throw Exception("Invalid carriage return in clipboard data");
+
   startMsg(msgTypeClientCutText);
   os->pad(3);
   os->writeU32(len);
diff --git a/common/rfb/SMsgReader.cxx b/common/rfb/SMsgReader.cxx
index 200350c..0c0e8b2 100644
--- a/common/rfb/SMsgReader.cxx
+++ b/common/rfb/SMsgReader.cxx
@@ -212,10 +212,10 @@
     vlog.error("Cut text too long (%d bytes) - ignoring", len);
     return;
   }
-  CharArray ca(len+1);
-  ca.buf[len] = 0;
+  CharArray ca(len);
   is->readBytes(ca.buf, len);
-  handler->clientCutText(ca.buf, len);
+  CharArray filtered(convertLF(ca.buf, len));
+  handler->clientCutText(filtered.buf, strlen(filtered.buf));
 }
 
 void SMsgReader::readQEMUMessage()
diff --git a/common/rfb/SMsgWriter.cxx b/common/rfb/SMsgWriter.cxx
index 6a2c2ba..f0748ff 100644
--- a/common/rfb/SMsgWriter.cxx
+++ b/common/rfb/SMsgWriter.cxx
@@ -80,6 +80,9 @@
 
 void SMsgWriter::writeServerCutText(const char* str, int len)
 {
+  if (memchr(str, '\r', len) != NULL)
+    throw Exception("Invalid carriage return in clipboard data");
+
   startMsg(msgTypeServerCutText);
   os->pad(3);
   os->writeU32(len);
diff --git a/common/rfb/VNCServerST.cxx b/common/rfb/VNCServerST.cxx
index c95c14f..7820aef 100644
--- a/common/rfb/VNCServerST.cxx
+++ b/common/rfb/VNCServerST.cxx
@@ -342,6 +342,8 @@
 
 void VNCServerST::serverCutText(const char* str, int len)
 {
+  if (memchr(str, '\r', len) != NULL)
+    throw Exception("Invalid carriage return in clipboard data");
   std::list<VNCSConnectionST*>::iterator ci, ci_next;
   for (ci = clients.begin(); ci != clients.end(); ci = ci_next) {
     ci_next = ci; ci_next++;
diff --git a/common/rfb/util.cxx b/common/rfb/util.cxx
index f52213b..f43a945 100644
--- a/common/rfb/util.cxx
+++ b/common/rfb/util.cxx
@@ -1,4 +1,5 @@
 /* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * Copyright 2011-2019 Pierre Ossman for Cendio AB
  * 
  * This is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -107,6 +108,61 @@
     dest[src ? destlen-1 : 0] = 0;
   }
 
+  char* convertLF(const char* src, size_t bytes)
+  {
+    char* buffer;
+    size_t sz;
+
+    char* out;
+    const char* in;
+    size_t in_len;
+
+    // Always include space for a NULL
+    sz = 1;
+
+    // Compute output size
+    in = src;
+    in_len = bytes;
+    while ((*in != '\0') && (in_len > 0)) {
+      if (*in != '\r') {
+        sz++;
+        in++;
+        in_len--;
+        continue;
+      }
+
+      if ((in_len == 0) || (*(in+1) != '\n'))
+        sz++;
+
+      in++;
+      in_len--;
+    }
+
+    // Alloc
+    buffer = new char[sz];
+    memset(buffer, 0, sz);
+
+    // And convert
+    out = buffer;
+    in = src;
+    in_len = bytes;
+    while ((*in != '\0') && (in_len > 0)) {
+      if (*in != '\r') {
+        *out++ = *in++;
+        in_len--;
+        continue;
+      }
+
+      if ((in_len == 0) || (*(in+1) != '\n'))
+        *out++ = '\n';
+
+      in++;
+      in_len--;
+    }
+
+    return buffer;
+  }
+
   unsigned msBetween(const struct timeval *first,
                      const struct timeval *second)
   {
diff --git a/common/rfb/util.h b/common/rfb/util.h
index 9e59bd3..de09669 100644
--- a/common/rfb/util.h
+++ b/common/rfb/util.h
@@ -1,4 +1,5 @@
 /* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * Copyright 2011-2019 Pierre Ossman for Cendio AB
  * 
  * This is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -83,6 +84,9 @@
   // Copies src to dest, up to specified length-1, and guarantees termination
   void strCopy(char* dest, const char* src, int destlen);
 
+  // Makes sure line endings are in a certain format
+
+  char* convertLF(const char* src, size_t bytes = (size_t)-1);
 
   // HELPER functions for timeout handling
 
diff --git a/unix/xserver/hw/vnc/RFBGlue.cc b/unix/xserver/hw/vnc/RFBGlue.cc
index 160177b..d9c456e 100644
--- a/unix/xserver/hw/vnc/RFBGlue.cc
+++ b/unix/xserver/hw/vnc/RFBGlue.cc
@@ -1,5 +1,5 @@
 /* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
- * Copyright 2011-2015 Pierre Ossman for Cendio AB
+ * Copyright 2011-2019 Pierre Ossman for Cendio AB
  * 
  * This is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -210,3 +210,17 @@
   }
   return 0;
 }
+
+char* vncConvertLF(const char* src, size_t bytes)
+{
+  try {
+    return convertLF(src, bytes);
+  } catch (...) {
+    return NULL;
+  }
+}
+
+void vncStrFree(char* str)
+{
+  strFree(str);
+}
diff --git a/unix/xserver/hw/vnc/RFBGlue.h b/unix/xserver/hw/vnc/RFBGlue.h
index a63afd0..8e70c68 100644
--- a/unix/xserver/hw/vnc/RFBGlue.h
+++ b/unix/xserver/hw/vnc/RFBGlue.h
@@ -1,5 +1,5 @@
 /* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
- * Copyright 2011-2015 Pierre Ossman for Cendio AB
+ * Copyright 2011-2019 Pierre Ossman for Cendio AB
  * 
  * This is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -49,6 +49,9 @@
 int vncGetSocketPort(int fd);
 int vncIsTCPPortUsed(int port);
 
+char* vncConvertLF(const char* src, size_t bytes);
+void vncStrFree(char* str);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/unix/xserver/hw/vnc/vncSelection.c b/unix/xserver/hw/vnc/vncSelection.c
index 4f3538d..5ddcaf0 100644
--- a/unix/xserver/hw/vnc/vncSelection.c
+++ b/unix/xserver/hw/vnc/vncSelection.c
@@ -1,4 +1,4 @@
-/* Copyright 2016 Pierre Ossman for Cendio AB
+/* Copyright 2016-2019 Pierre Ossman for Cendio AB
  * 
  * This is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -415,13 +415,22 @@
     else if (vncHasAtom(xaUTF8_STRING, (const Atom*)prop->data, prop->size))
       vncSelectionRequest(selection, xaUTF8_STRING);
   } else if (target == xaSTRING) {
+    char* filtered;
+
     if (prop->format != 8)
       return;
     if (prop->type != xaSTRING)
       return;
 
-    vncServerCutText(prop->data, prop->size);
+    filtered = vncConvertLF(prop->data, prop->size);
+    if (filtered == NULL)
+      return;
+
+    vncServerCutText(filtered, strlen(filtered));
+
+    vncStrFree(filtered);
   } else if (target == xaUTF8_STRING) {
+    char *filtered;
     unsigned char* buffer;
     unsigned char* out;
     size_t len;
@@ -470,9 +479,14 @@
       }
     }
 
-    vncServerCutText((const char*)buffer, len);
-
+    filtered = vncConvertLF(buffer, len);
     free(buffer);
+    if (filtered == NULL)
+      return;
+
+    vncServerCutText(filtered, strlen(filtered));
+
+    vncStrFree(filtered);
   }
 }
 
diff --git a/vncviewer/Viewport.cxx b/vncviewer/Viewport.cxx
index 5df5c79..15a3ec4 100644
--- a/vncviewer/Viewport.cxx
+++ b/vncviewer/Viewport.cxx
@@ -1,5 +1,5 @@
 /* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
- * Copyright 2011-2014 Pierre Ossman for Cendio AB
+ * Copyright 2011-2019 Pierre Ossman for Cendio AB
  * 
  * This is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -549,7 +549,7 @@
 
 int Viewport::handle(int event)
 {
-  char *buffer;
+  char *buffer, *filtered;
   int ret;
   int buttonMask, wheelMask;
   DownMap::const_iterator iter;
@@ -564,22 +564,26 @@
     ret = fl_utf8toa(Fl::event_text(), Fl::event_length(), buffer,
                      Fl::event_length() + 1);
     assert(ret < (Fl::event_length() + 1));
+    filtered = convertLF(buffer, ret);
+    delete [] buffer;
 
     if (!hasFocus()) {
-      pendingClientCutText = buffer;
+      pendingClientCutText = new char[strlen(filtered) + 1];
+      strcpy((char*)pendingClientCutText, filtered);
+      strFree(filtered);
       return 1;
     }
 
-    vlog.debug("Sending clipboard data (%d bytes)", (int)strlen(buffer));
+    vlog.debug("Sending clipboard data (%d bytes)", (int)strlen(filtered));
 
     try {
-      cc->writer()->writeClientCutText(buffer, ret);
+      cc->writer()->writeClientCutText(filtered, strlen(filtered));
     } catch (rdr::Exception& e) {
       vlog.error("%s", e.str());
       exit_vncviewer(e.str());
     }
 
-    delete [] buffer;
+    strFree(filtered);
 
     return 1;
 
diff --git a/win/rfb_win32/Clipboard.cxx b/win/rfb_win32/Clipboard.cxx
index 0e29062..fca6c1d 100644
--- a/win/rfb_win32/Clipboard.cxx
+++ b/win/rfb_win32/Clipboard.cxx
@@ -1,4 +1,5 @@
 /* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * Copyright 2012-2019 Pierre Ossman for Cendio AB
  * 
  * This is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -35,18 +36,6 @@
 //
 
 char*
-dos2unix(const char* text) {
-  int len = strlen(text)+1;
-  char* unix = new char[strlen(text)+1];
-  int i, j=0;
-  for (i=0; i<len; i++) {
-    if (text[i] != '\x0d')
-      unix[j++] = text[i];
-  }
-  return unix;
-}
-
-char*
 unix2dos(const char* text) {
   int len = strlen(text)+1;
   char* dos = new char[strlen(text)*2+1];
@@ -126,8 +115,7 @@
               if (!clipdata) {
                 notifier->notifyClipboardChanged(0, 0);
               } else {
-                CharArray unix_text;
-                unix_text.buf = dos2unix(clipdata);
+                CharArray unix_text(convertLF(clipdata, strlen(clipdata)));
                 removeNonISOLatin1Chars(unix_text.buf);
                 notifier->notifyClipboardChanged(unix_text.buf, strlen(unix_text.buf));
               }