From a recent audit report by Social Security's Office of Inspector General:
In September 2001, President Bush signed Executive Order (EO) 13224, Blocking Property and Prohibiting Transactions with Persons Who Commit, Threaten to Commit, or Support Terrorism, giving the Government a means of disrupting the financial support network for terrorists and terrorist organizations. On December 18, 2002, the Department of the Treasury (Treasury) issued Financial Manual, Bulletin No. 2003 04, notifying Federal agencies of the implementation of EO 13224. The Bulletin states Federal agencies must not make payments or draw checks or warrants payable to an individual or organization listed on the Office of Foreign Assets Control’s (OFAC) Website of persons who commit, threaten to commit, or support terrorism.
In 2005, we reviewed the actions SSA had taken to ensure it was not making payments to individuals or organizations on OFAC’s Website. We determined that SSA had not taken all of the necessary steps to ensure it was not making such payments. Specifically, SSA had not matched payment records for its Title II and XVI programs or its Third Party Payment System (TPPS) with OFAC’s file. ...
However, SSA does not screen other payments because it believes that neither EO 13224 nor the Social Security Act gives the Agency authority to withhold or stop benefit payments when a person is identified on the OFAC list as a terrorist. Additionally, the Agency believes it is taking all appropriate measures in its authority to carry out the provisions of EO 13224. ...
In September 2009, SSA began providing Treasury with identifying information to enable OFAC screening of SSA recipients who reside outside the United States and receive payment by direct deposit at a foreign financial institution. An official from SSA‘s Office of Financial Policy and Operations told us the Agency began providing Treasury with such information because of new rules governing international direct deposits. These rules were written to ensure that international transactions undergo the screening required by OFAC to fight terrorist financing and money laundering. According to this official, SSA is also working with Treasury to develop a similar process to screen recipients who reside outside the United States and receive payment by direct deposit at a domestic financial institution. However, this official told us that Treasury had not decided whether it will screen these payments or request that SSA do so. ...
Accordingly, we recommend that SSA work with DoJ, Treasury, OMB, and, if necessary, others to resolve any issues the Agency believes prevent it from screening payments to individuals identified on OFAC’s list.
I guess we can expect a Congressional hearing on this if Republicans take control of the House of Representatives next year.