1 files changed, 3 insertions, 0 deletions
diff --git a/lib/net/ftp.rb b/lib/net/ftp.rb
index cfd8cf7945..bd89956d36 100644
--- a/lib/net/ftp.rb
+++ b/lib/net/ftp.rb
@@ -295,6 +295,9 @@ module Net
       if @debug_mode
         print "put: ", sanitize(line), "\n"
       end
+      if /[\r\n]/ =~ line
+        raise ArgumentError, "A line must not contain CR or LF"
+      end
       line = line + CRLF
       @sock.write(line)
     end