Thursday 21 September 2017

Malware spam: "Invoice RE-2017-09-21-00xxx" from "Amazon Marketplace"

This fake Amazon spam comes with a malicious attachment:

Subject:       Invoice RE-2017-09-21-00794
From:       "Amazon Marketplace" [yAhbPDAoufvZE@marketplace.amazon.co.uk]
Date:       Thu, September 21, 2017 9:21 am
Priority:       Normal

------------- Begin message -------------

Dear customer,

We want to use this opportunity to first say "Thank you very much for your purchase!"

Attached to this email you will find your invoice.

Kindest of regards,
your Amazon Marketplace

==



[commMgrHmdToken:EVDOOCETFBECA]

------------- End message -------------

For Your Information: To help arbitrate disputes and preserve trust and safety, we
retain all messages buyers and sellers send through Amazon.co.uk. This includes your
response to the message below. For your protection we recommend that you only
communicate with buyers and sellers using this method.

Important: Amazon.co.uk's A-to-z Guarantee only covers third-party purchases paid
for through our Amazon Payments system via our Shopping Cart or 1-Click. Our
Guarantee does not cover any payments that occur off Amazon.co.uk including wire
transfers, money orders, cash, check, or off-site credit card transactions.

We want you to buy with confidence whenever you purchase products on Amazon.co.uk.
Learn more about Safe Online Shopping
(http://www.amazon.co.uk/gp/help/customer/display.html?nodeId=11081621) and our safe
buying guarantee
(http://www.amazon.co.uk/gp/help/customer/display.html?nodeId=3149571).



[commMgrTok:EVDOOCETFBECA]
Attached is a .7z archive file with a name that matches the one quoted in the subject line. So far I have seen just two versions of this, each containing a malicious script (sample here and here). These scripts have a detection rate of about 13/58 and they can been seen attempted to download a component from:

ahlbrandt.eu/IUGiwe8?
fulcar.info/p66/IUGiwe8
accuflowfloors.com/IUGiwe8?
aetozi.gr/IUGiwe8?
agricom.it/IUGiwe8?


An executable is dropped (Locky ransomware) with a detection rate of 18/64. Although Hybrid Analysis [1] [2] clearly shows the ransomware, no C2s are currently available (it turns out there aren't any).

UPDATE - additional download locations:
81552.com/IUGiwe8
adr-werbetechnik.de/IUGiwe8
afmance.it/IUGiwe8
afradem.com/IUGiwe8
agriturismobellaria.net/IUGiwe8
agro-kerler.de/IUGiwe8
moonmusic.com.au/IUGiwe8

4 comments:

  1. SPF test on the email gateway will block these no bother.


    -------------------------------------------------------------------------------

    -- EVENT SUMMARY --
    Time: 21/09/2017 10:04:33 GMT+0100 GMT Daylight Time
    Sender Email: ZYvSEQFNDqZUNSJ@marketplace.amazon.co.uk
    Recipient Email: [EDITED]
    Related IP: 115.79.66.123
    Action: Rejected
    Email Subject: (not available)

    -- EVENT MESSAGE --
    Blacklisted by the SPF Test (sender forged per policy of "marketplace.amazon.co.uk", SPF result: "softfail").


    -------------------------------------------------------------------------------

    ReplyDelete
  2. In the last hour 1 has 100 attempts like that - all to majority to valid email addresses and all coming from different IPs.

    110.225.27.74
    115.79.66.123
    203.210.244.147
    58.84.60.183
    113.161.25.6
    121.52.158.182
    117.7.92.165
    93.137.23.127
    14.174.171.236
    92.53.53.124
    27.78.211.5
    113.175.22.171
    122.177.43.116
    115.76.240.205
    14.162.105.43
    109.92.23.251
    109.92.23.251
    113.161.144.216
    113.169.82.145
    103.38.4.238
    37.6.1.194
    14.186.82.170
    182.64.131.226
    123.16.2.55
    27.64.25.11
    183.87.89.163
    122.178.120.197
    94.112.254.74
    14.171.234.18
    121.243.95.190
    58.187.4.118
    115.73.24.192
    123.16.228.193
    160.202.159.244
    103.247.109.49
    122.180.185.38
    118.136.161.196
    195.120.34.49
    14.175.89.197
    116.74.52.44
    27.68.41.194
    187.162.106.231
    85.155.154.203
    14.187.168.136
    85.111.77.173
    200.94.47.86
    122.163.25.81
    14.234.233.140
    202.83.57.93
    122.180.9.202
    116.206.29.112
    14.97.48.159
    59.90.152.130
    82.208.162.136
    195.175.55.106
    82.208.162.136
    213.14.244.28
    82.208.162.136
    117.1.189.212
    113.160.165.72
    122.167.219.80
    14.237.153.241
    103.232.238.244
    175.107.20.227
    117.4.250.205
    1.186.46.26
    122.171.24.66
    117.4.250.205
    14.185.222.115
    88.255.168.165
    209.88.90.24
    151.237.104.18
    122.177.196.6
    122.165.119.97
    181.124.114.84
    122.160.116.12
    94.183.237.243
    192.140.8.21
    105.146.188.117
    118.70.128.93
    105.146.188.117
    113.160.101.57
    14.161.15.60
    113.190.146.121
    85.105.225.239
    115.79.82.202
    14.187.219.146
    113.161.212.118
    94.183.21.38
    1.186.177.203
    175.107.20.17
    14.162.142.55
    27.147.217.58
    94.183.216.184
    80.21.191.130
    122.174.167.212
    113.161.58.71
    117.1.182.244
    14.162.114.130
    202.51.190.186
    182.64.173.185
    27.72.3.95
    125.22.105.170
    14.177.68.56
    197.237.12.150
    118.71.172.246
    113.186.121.208
    188.158.252.37
    188.158.252.37
    114.69.253.4
    113.170.235.241
    219.92.20.28
    59.177.104.199
    111.94.45.103

    ReplyDelete
  3. @naszfranio This will be the Necurs botnet. IPs will be all over the place.

    Yes, checking SPF records should block it. Also, blocking .7z files would probably not cause much a problem, these are commonly used for Locky right at the moment.

    ReplyDelete
  4. The SPF softfail mechanism (in my experience by far the most widely used SPF configuration) does not actually assert a failing message is a spoof.

    The specification reads:

    8.5. Softfail

    A "softfail" result ought to be treated as somewhere between "fail"
    and "neutral"/"none". The ADMD believes the host is not authorized
    but is not willing to make a strong policy statement. Receiving
    software SHOULD NOT reject the message based solely on this result,
    but MAY subject the message to closer scrutiny than normal.

    If you pass an SPF check with the hardfail or softfail mechanism - you are considered a legitimate sender
    if you fail an SPF check with the softfail mechanism - you might be a legitimate sender
    if you fail an SPF check with the hardfail mechanism - you are not a legitimate sender


    It would be better for companies like Amazon to use the hardfail mechanism for this reason to protect their brand as the softfail mechanism does not adequately do so.


    ReplyDelete