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