From 109bc87ffbdfd5ef16e4d9ca9d0ee04fbb901190 Mon Sep 17 00:00:00 2001
From: William Vu <William_Vu@rapid7.com>
Date: Fri, 2 Mar 2018 13:28:20 -0600
Subject: [PATCH] Check for nil, EOFError, and zero-length response

---
 modules/exploits/linux/telnet/netgear_telnetenable.rb | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/modules/exploits/linux/telnet/netgear_telnetenable.rb b/modules/exploits/linux/telnet/netgear_telnetenable.rb
index 20553f3263..70feb09e85 100644
--- a/modules/exploits/linux/telnet/netgear_telnetenable.rb
+++ b/modules/exploits/linux/telnet/netgear_telnetenable.rb
@@ -77,7 +77,13 @@ class MetasploitModule < Msf::Exploit::Remote
       begin
         connect
 
-        if sock.get_once.length == 0
+        res = begin
+          sock.get_once || ''
+        rescue EOFError
+          ''
+        end
+
+        if res.length == 0
           print_good('Detected telnetenabled on TCP')
         else
           print_good('Detected telnetd on TCP')