Considerable reliability improvements for ticketbleed: if a handshake server hello

was received, testssl.sh tries 3 times to get memory from the server, If
the server returns different memory it's highly likely vulnerable.
(some more vulnerable devices to test against would be appreciated).

This is the default now -- all other hosts are mostly labled as OK.

Parsing SERVICE should be a little faster and more reliable

Increased needed debug level for output @ parse_tls_serverhello
This commit is contained in:
Dirk 2017-05-15 19:47:13 +02:00
parent b694930fc2
commit e8b5a82c7e
1 changed files with 113 additions and 82 deletions

View File

@ -1143,6 +1143,7 @@ out_row_aligned_max_width_by_entry() {
tmpfile_handle() {
local savefile="$2"
[[ -z "$savefile" ]] && savefile=$TMPFILE
#FIXME: make sure/find out if we do not need $TEMPDIR/$NODEIP.$1" if debug=0. We would save fs access here
mv $savefile "$TEMPDIR/$NODEIP.$1" 2>/dev/null
[[ $ERRFILE =~ dev.null ]] && return 0 || \
mv $ERRFILE "$TEMPDIR/$NODEIP.$(sed 's/\.txt//g' <<<"$1").errorlog" 2>/dev/null
@ -1271,17 +1272,17 @@ service_detection() {
local addcmd=""
if ! $CLIENT_AUTH; then
# SNI is nonsense for !HTTPS but fortunately for other protocols s_client doesn't seem to care
# SNI is not standardardized for !HTTPS but fortunately for other protocols s_client doesn't seem to care
[[ ! "$1" =~ ssl ]] && addcmd="$SNI"
printf "$GET_REQ11" | $OPENSSL s_client $1 -quiet $BUGS -connect $NODEIP:$PORT $PROXY $addcmd >$TMPFILE 2>$ERRFILE &
wait_kill $! $HEADER_MAXSLEEP
was_killed=$?
head $TMPFILE | grep -aq ^HTTP && SERVICE=HTTP
head $TMPFILE | grep -aq SMTP && SERVICE=SMTP
head $TMPFILE | grep -aq POP && SERVICE=POP
head $TMPFILE | grep -aq IMAP && SERVICE=IMAP
head $TMPFILE | egrep -aqw "Jive News|InterNetNews|NNRP|INN" && SERVICE=NNTP
debugme head -50 $TMPFILE
head $TMPFILE | grep -aq '^HTTP\/' && SERVICE=HTTP
[[ -z "$SERVICE" ]] && head $TMPFILE | grep -aq SMTP && SERVICE=SMTP
[[ -z "$SERVICE" ]] && head $TMPFILE | grep -aq POP && SERVICE=POP
[[ -z "$SERVICE" ]] && head $TMPFILE | grep -aq IMAP && SERVICE=IMAP
[[ -z "$SERVICE" ]] && head $TMPFILE | egrep -aqw "Jive News|InterNetNews|NNRP|INN" && SERVICE=NNTP
debugme head -50 $TMPFILE | sed -e '/<HTML>/,$d' -e '/<html>/,$d' -e '/<XML/,$d' -e '/<xml/,$d' -e '/<\?XML/,$d' -e '/<\?xml/,$d' -e '/<\!DOCTYPE/,$d' -e '/<\!doctype/,$d'
fi
out " Service detected: $CORRECT_SPACES"
@ -1361,8 +1362,8 @@ run_http_header() {
debugme echo "$NOW_TIME: $HTTP_TIME"
# delete from pattern til the end. We ignore any leading spaces (e.g. www.amazon.de)
sed -e '/<HTML>/,$d' -e '/<html>/,$d' -e '/<XML/,$d' -e '/<?XML/,$d' \
-e '/<xml/,$d' -e '/<?xml/,$d' -e '/<\!DOCTYPE/,$d' -e '/<\!doctype/,$d' $HEADERFILE >$HEADERFILE.2
sed -e '/<HTML>/,$d' -e '/<html>/,$d' -e '/<XML/,$d' -e '/<xml/,$d' \
-e '/<\?XML/,$d' -e '/<?xml/,$d' -e '/<\!DOCTYPE/,$d' -e '/<\!doctype/,$d' $HEADERFILE >$HEADERFILE.2
#### ^^^ Attention: the filtering for the html body only as of now, doesn't work for other content yet
mv $HEADERFILE.2 $HEADERFILE # sed'ing in place doesn't work with BSD and Linux simultaneously
ret=0
@ -7593,9 +7594,9 @@ parse_tls_serverhello() {
msg_len=2*$(hex2dec "${tls_hello_ascii:i:4}")
i=$i+4
if [[ $DEBUG -ge 2 ]]; then
echo " tls_protocol (reclyr): 0x$tls_protocol"
tm_out " tls_content_type: 0x$tls_content_type"
if [[ $DEBUG -ge 3 ]]; then
echo " protocol (rec. layer): 0x$tls_protocol"
echo " tls_content_type: 0x$tls_content_type"
case $tls_content_type in
15) tmln_out " (alert)" ;;
16) tmln_out " (handshake)" ;;
@ -7716,7 +7717,7 @@ parse_tls_serverhello() {
# Now extract just the server hello, certificate, certificate status,
# and server key exchange handshake messages.
tls_handshake_ascii_len=${#tls_handshake_ascii}
if [[ $DEBUG -ge 2 ]] && [[ $tls_handshake_ascii_len -gt 0 ]]; then
if [[ $DEBUG -ge 3 ]] && [[ $tls_handshake_ascii_len -gt 0 ]]; then
echo "TLS handshake messages:"
fi
for (( i=0; i<tls_handshake_ascii_len; i=i+msg_len )); do
@ -7736,7 +7737,7 @@ parse_tls_serverhello() {
msg_len=2*$(hex2dec "${tls_handshake_ascii:i:6}")
i=$i+6
if [[ $DEBUG -ge 2 ]]; then
if [[ $DEBUG -ge 3 ]]; then
tm_out " handshake type: 0x${tls_msg_type}"
case $tls_msg_type in
00) tmln_out " (hello_request)" ;;
@ -7993,7 +7994,7 @@ parse_tls_serverhello() {
fi
[[ -n "$tls_extensions" ]] && echo -e "$tls_extensions" >> $TMPFILE
if [[ $DEBUG -ge 2 ]]; then
if [[ $DEBUG -ge 3 ]]; then
echo "TLS server hello message:"
if [[ $DEBUG -ge 4 ]]; then
echo " tls_protocol: 0x$tls_protocol2"
@ -9120,13 +9121,17 @@ run_ticketbleed() {
local sid="x00,x0B,xAD,xC0,xDE,x00," # some abitratry bytes
local len_sid="$(( ${#sid} / 4))"
local xlen_sid="$(dec02hex $len_sid)"
local -i len_tckt_tls=0
local -i len_tckt_tls=0 nr_sid_detected=0
local xlen_tckt_tls="" xlen_handshake_record_layer="" xlen_handshake_ssl_layer=""
local -i len_handshake_record_layer=0
local cve="CVE-2016-9244"
local cwe="CWE-200"
local hint=""
local tls_version=""
local i
local -a memory sid_detected
local early_exit=true
local ret=0
[[ $VULN_COUNT -le $VULN_THRESHLD ]] && outln && pr_headlineln " Testing for Ticketbleed vulnerability " && outln
pr_bold " Ticketbleed"; out " ($cve), experiment. "
@ -9163,20 +9168,19 @@ run_ticketbleed() {
SSLv3) tls_hexcode="x03, x00" ;;
esac
fi
debugme echo "using protocol $tls_hexcode"
debugme echo -e "\nusing protocol $tls_hexcode"
session_tckt_tls="$(get_session_ticket_tls)"
debugme echo " session ticket TLS \"$session_tckt_tls\""
if [[ "$session_tckt_tls" == "," ]]; then
pr_done_best "not vulnerable (OK)"
outln ", no session tickets"
fileout "ticketbleed" "OK" "Ticketbleed: not vulnerable" "$cve" "$cwe"
debugme echo " session ticket TLS \"$session_tckt_tls\""
return 0
fi
len_tckt_tls=${#session_tckt_tls}
len_tckt_tls=$(( len_tckt_tls / 4))
xlen_tckt_tls="$(dec02hex $len_tckt_tls)"
len_handshake_record_layer="$(( len_sid + len_ch + len_tckt_tls ))"
xlen_handshake_record_layer="$(dec04hex "$len_handshake_record_layer")"
@ -9210,7 +9214,6 @@ run_ticketbleed() {
x03, x90, x9f, x77, x04, x33, xff, xff,
$xlen_sid, # Session ID length
$sid
x00, x6a, # Cipher suites length 106
# 53 Cipher suites
xc0,x14, xc0,x13, xc0,x0a, xc0,x21,
@ -9271,71 +9274,102 @@ run_ticketbleed() {
# Extension: Heartbeat
x00, x0f, x00, x01, x01"
fd_socket 5 || return 6
debugme tmln_out "\nsending client hello "
socksend "$client_hello" 0
# we do 3 client hellos, and see whether different memmory is returned
for i in 1 2 3; do
fd_socket 5 || return 6
debugme tmln_out "\nsending client hello "
socksend "$client_hello" 0
debugme tmln_out "\nreading server hello (ticketbleed reply)"
if "$FAST_SOCKET"; then
tls_hello_ascii=$(sockread_fast 32768)
else
sockread_serverhello 32768 $CCS_MAX_WAITSOCK
tls_hello_ascii=$(hexdump -v -e '16/1 "%02X"' "$SOCK_REPLY_FILE")
fi
[[ "$DEBUG" -ge 5 ]] && echo "$tls_hello_ascii"
if [[ "$DEBUG" -ge 4 ]]; then
echo "============================="
echo "$tls_hello_ascii"
echo "============================="
fi
if [[ "${tls_hello_ascii:0:2}" == "16" ]]; then
debugme echo -n "Handshake (TLS version: ${tls_hello_ascii:2:4}), "
if [[ "${tls_hello_ascii:10:6}" == 020000 ]]; then
debugme echo -n "ServerHello -- "
debugme tmln_out "\nreading server hello (ticketbleed reply)"
if "$FAST_SOCKET"; then
tls_hello_ascii=$(sockread_fast 32768)
else
debugme echo -n "Message type: ${tls_hello_ascii:10:6} -- "
sockread_serverhello 32768 $CCS_MAX_WAITSOCK
tls_hello_ascii=$(hexdump -v -e '16/1 "%02X"' "$SOCK_REPLY_FILE")
fi
sid_detected="${tls_hello_ascii:88:32}"
sid_input=$(sed -e 's/x//g' -e 's/,//g' <<< "$sid")
if [[ "$DEBUG" -ge 2 ]]; then
echo
echo "TLS version, record layer: ${tls_hello_ascii:18:4}"
echo "Random bytes / timestamp: ${tls_hello_ascii:22:64}"
echo "Session ID: $sid_detected"
[[ "$DEBUG" -ge 5 ]] && echo "$tls_hello_ascii"
if [[ "$DEBUG" -ge 4 ]]; then
echo "============================="
echo "$tls_hello_ascii"
echo "============================="
fi
if grep -q $sid_input <<< "$sid_detected"; then
pr_svrty_critical "VULNERABLE (NOT ok)"
fileout "ticketbleed" "CRITICAL" "Ticketbleed: VULNERABLE" "$cve" "$cwe" "$hint"
else
out "likely "
if [[ "${tls_hello_ascii:0:2}" == "15" ]]; then
debugme echo -n "TLS Alert ${tls_hello_ascii:10:4} (TLS version: ${tls_hello_ascii:2:4}) -- "
pr_done_best "not vulnerable (OK)"
out " -- but received a session ID back which shouldn't happen"
fileout "ticketbleed" "OK" "Ticketbleed: not vulnerable, but with a session ID reply which shouldn't happen" "$cve" "$cwe"
fi
elif [[ "${tls_hello_ascii:0:2}" == "15" ]]; then
debugme echo -n "TLS Alert ${tls_hello_ascii:10:4} (TLS version: ${tls_hello_ascii:2:4}) -- "
pr_done_best "not vulnerable (OK)"
fileout "ticketbleed" "OK" "Ticketbleed: not vulnerable" "$cve" "$cwe"
else
ret=7
pr_warning "test failed"
if [[ -z "${tls_hello_ascii:0:2}" ]]; then
out ": reply empty"
fileout "ticketbleed" "WARN" "Ticketbleed: test failed with empty ServerHello" "$cve" "$cwe"
fileout "ticketbleed" "OK" "Ticketbleed: not vulnerable" "$cve" "$cwe"
break
elif [[ -z "${tls_hello_ascii:0:2}" ]]; then
pr_done_best "not vulnerable (OK)"
out ", reply empty"
fileout "ticketbleed" "OK" "Ticketbleed: not vulnerable" "$cve" "$cwe"
break
elif [[ "${tls_hello_ascii:0:2}" == "16" ]]; then
early_exit=false
debugme echo -n "Handshake (TLS version: ${tls_hello_ascii:2:4}), "
if [[ "${tls_hello_ascii:10:6}" == 020000 ]]; then
debugme echo -n "ServerHello -- "
else
debugme echo -n "Message type: ${tls_hello_ascii:10:6} -- "
fi
sid_input=$(sed -e 's/x//g' -e 's/,//g' <<< "$sid")
sid_detected[i]="${tls_hello_ascii:88:32}"
memory[i]="${tls_hello_ascii:$((88+ len_sid*2)):$((32 - len_sid*2))}"
if [[ "$DEBUG" -ge 2 ]]; then
echo
echo "TLS version, record layer: ${tls_hello_ascii:18:4}"
echo "Session ID: ${sid_detected[i]}"
echo "memory: ${memory[i]}"
echo -n "$sid_input in SID: " ;
grep -q $sid_input <<< "${sid_detected[i]}" && echo "yes" || echo "no"
fi
[[ "$DEBUG" -ge 1 ]] && echo $tls_hello_ascii >$TEMPDIR/$FUNCNAME.tls_hello_ascii${i}.txt
else
ret=7
pr_warning "test failed"
out " around line $LINENO (debug info: ${tls_hello_ascii:0:2}, ${tls_hello_ascii:2:10})"
fileout "ticketbleed" "WARN" "Ticketbleed: test failed, around $LINENO (debug info: ${tls_hello_ascii:0:2}, ${tls_hello_ascii:2:10})" "$cve" "$cwe"
break
fi
debugme echo "sending close_notify..."
if [[ ${tls_hello_ascii:18:4} == "0300" ]]; then
socksend ",x15, x03, x00, x00, x02, x02, x00" 0
else
socksend ",x15, x03, x01, x00, x02, x02, x00" 0
fi
close_socket
done
if ! "$early_exit"; then
# here we test the replys if a TLS server hello was received >1x
for i in 1 2 3 ; do
if grep -q $sid_input <<< "${sid_detected[i]}"; then
# was our faked TLS SID returned?
nr_sid_detected+=1
fi
done
if [[ $nr_sid_detected -eq 3 ]]; then
if [[ ${memory[1]} != ${memory[2]} ]] && [[ ${memory[2]} != ${memory[3]} ]]; then
pr_svrty_critical "VULNERABLE (NOT ok)"
fileout "ticketbleed" "CRITICAL" "Ticketbleed: VULNERABLE" "$cve" "$cwe" "$hint"
else
pr_done_best "not vulnerable (OK)"
out ", memory fragments do not differ"
fileout "ticketbleed" "OK" "Ticketbleed: not vulnerable, session IDs were returned but memory fragments do not differ" "$cve" "$cwe"
fi
else
if [[ "$DEBUG" -ge 2 ]]; then
echo
pr_warning "test failed, non reproducible results!"
else
pr_warning "test failed, non reproducible results!"
out " Please run again w \"--debug=2\" (# of faked TLS SIDs detected: $nr_sid_detected)"
fi
fileout "ticketbleed" "WARN" "Ticketbleed: # of TLS Session IDs detected: $nr_sid_detected, ${sid_detected[1]},${sid_detected[2]},${sid_detected[3]}" "$cve" "$cwe"
ret=7
fi
fi
outln
if [[ "$DEBUG" -ge 1 ]]; then
echo $tls_hello_ascii >$FUNCNAME.txt
tmpfile_handle $FUNCNAME.txt
fi
close_socket
return $ret
}
@ -11952,8 +11986,7 @@ determine_service() {
datebanner " Start"
outln
if [[ -z "$1" ]]; then
# no STARTTLS.
if [[ -z "$1" ]]; then # no STARTTLS.
determine_optimal_proto "$1"
$SNEAKY && \
ua="$UA_SNEAKY" || \
@ -11963,12 +11996,11 @@ determine_service() {
# GET_REQ10="GET $URL_PATH HTTP/1.0\r\nUser-Agent: $ua\r\nConnection: Close\r\nAccept: text/*\r\n\r\n"
# HEAD_REQ10="HEAD $URL_PATH HTTP/1.0\r\nUser-Agent: $ua\r\nAccept: text/*\r\n\r\n"
service_detection $OPTIMAL_PROTO
else
# STARTTLS
else # STARTTLS
if [[ "$1" == postgres ]]; then
protocol="postgres"
else
protocol=${1%s} # strip trailing 's' in ftp(s), smtp(s), pop3(s), etc
protocol=${1%s} # strip trailing 's' in ftp(s), smtp(s), pop3(s), etc
fi
case "$protocol" in
ftp|smtp|pop3|imap|xmpp|telnet|ldap|postgres)
@ -11981,7 +12013,7 @@ determine_service() {
if ! "$HAS_XMPP"; then
fatal "Your $OPENSSL does not support the \"-xmpphost\" option" -5
fi
STARTTLS="$STARTTLS -xmpphost $XMPP_HOST" # it's a hack -- instead of changing calls all over the place
STARTTLS="$STARTTLS -xmpphost $XMPP_HOST" # small hack -- instead of changing calls all over the place
# see http://xmpp.org/rfcs/rfc3920.html
fi
fi
@ -11993,7 +12025,7 @@ determine_service() {
fi
$OPENSSL s_client -connect $NODEIP:$PORT $PROXY $BUGS $STARTTLS 2>$ERRFILE >$TMPFILE </dev/null
if [[ $? -ne 0 ]]; then
debugme cat $TMPFILE
debugme cat $TMPFILE | head -25
outln
fatal " $OPENSSL couldn't establish STARTTLS via $protocol to $NODEIP:$PORT" -2
fi
@ -12009,7 +12041,6 @@ determine_service() {
;;
esac
fi
#outln
tmpfile_handle $FUNCNAME.txt
return 0 # OPTIMAL_PROTO, GET_REQ*/HEAD_REQ* is set now