On June 15, 2015, we sent an advisory regarding targeted social engineering/phishing attacks of elevated sophistication attempting to engineer fraudulent wire transfers across our clients. Since then, media reports have created better visibility into these types of attacks. On August 27, 2015 Brian Krebs (of krebsonsecurity.com) posted a summary of an FBI news release: (http://krebsonsecurity.com/2015/08/fbi-1-2b-lost-to-business-email-scams/).
Despite additional visibility and media coverage, these attacks continue to find success.
Over the past two months, we have analyzed over a dozen of these recent attack attempts within our client base, and have additional details to share:
- The vast majority of these attacks are initiated on Thursdays and Fridays. It is our belief that the proximity to the weekend and employee’s focus therein may be factors in play here.
- Vistaprint/Tucows seem to be among the most favoured domain reseller and registrar pair for these false domains.
- Note that while the vast majority of inbound wire transfer attempts are direct requests for money, there have been examples of fraudulent wire transfers for goods easily fungible. These include SIP trunk (Voice Over IP) services to be resold.
- While false domains for email are always created and used, on occasion the attacker will duplicate the website as well.
- When false domains are created, while they often will use similar misspellings (e.g. “n” where “m” is usually used), they are also using correct spelling of rebranded names. For example, if your firm’s name is XYZ Capital Partners with a domain name of xyzcapitalpartners.com, false domains created might be registered as either XYZ Capital Management (xyzcapitalmgmt.com) or XYZ Capital Group (xyzcapitalgroup.com).
As these types of attack rely upon tricking people with email content and contains no technical exploits, there are very few technical remedies. However, we recommend the following additional options:
- Identify all staff with the capability to set up and/or confirm wire transfers and regularly train them to watch for these attacks.
- Heightened awareness is needed especially if the requests arrive on days immediately preceding a weekend or a holiday.
All should watch the three most common Neuro-Linguistic Programming (NLP) techniques attackers use to gain information:
For example, a false request might look as though the CEO of the company has sent an urgent request to have money transferred, however they are in a board meeting and request that they are not disturbed. Existence of any two of these three NLP characteristics may indicate a potential fraud situation and should require further critical analysis.
We also recommend the following out-of-band verification methods:
- Whenever an executive requests a wire transfer, a confirmation call initiated by the recipient must be made before the wire is initiated. An inbound phone call from the executive is not sufficient (as inbound phone numbers can be spoofed).
- For each of the most-targeted individuals in the firm (including all of the senior executive, finance and accounting teams) a unique and discreet confirmation phrase should be used when a legitimate (though uncommon) wire transfer is needed. This uncommon catchphrase can be used to provide a level of non-repudiation during the request. This could include something along the lines of “Go Yankees!” within the body of the request. This may be most effective if the targeted individuals infrequently effect wire transfers.