Bullrun (decryption program)

National Security Agency surveillance
Map of global NSA data collection as of 2007[update], with countries subject to the most data collection shown in red
Programs Pre-1978 ECHELON MINARET SHAMROCK PROMIS Since 1978 Upstream collection BLARNEY FAIRVIEW Main Core ThinThread Genoa Since 1990 RAMPART-A Since 1998 Tailored Access Operations Since 2001 OAKSTAR STORMBREW Trailblazer Turbulence Genoa II Total Information Awareness President's Surveillance Program Terrorist Surveillance Program Since 2007 PRISM Dropmire Stateroom Bullrun MYSTIC Databases, tools etc. PINWALE MARINA Main Core MAINWAY TRAFFICTHIEF DISHFIRE XKeyscore ICREACH BOUNDLESSINFORMANT GCHQ collaboration MUSCULAR Tempora
Legislation Safe Streets Act Privacy Act of 1974 FISA ECPA Patriot Act Homeland Security Act Protect America Act of 2007 FISA Amendments Act of 2008
Institutions FISC Senate Intelligence Committee National Security Council
Lawsuits ACLU v. NSA Hepting v. AT&T Jewel v. NSA Clapper v. Amnesty Klayman v. Obama ACLU v. Clapper Wikimedia v. NSA US v. Moalin
Whistleblowers William Binney Thomas Drake Mark Klein Thomas Tamm Russ Tice Edward Snowden
Publication 2005 warrantless surveillance scandal Global surveillance disclosures (2013–present)
Related Cablegate Surveillance of reporters Mail tracking UN diplomatic spying Insider Threat Program Mass surveillance in the United States Mass surveillance in the United Kingdom
Concepts SIGINT Metadata
Collaboration United States CSS CYBERCOM DOJ FBI CIA DHS IAO Five Eyes CSEC GCHQ ASD GCSB Other DGSE BND
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Bullrun (stylized BULLRUN) is a clandestine, highly classified program to crack encryption of online communications and data, which is run by the United States National Security Agency (NSA).^[1][2] The British Government Communications Headquarters (GCHQ) has a similar program codenamed Edgehill. According to the Bullrun classification guide published by The Guardian, the program uses multiple methods including computer network exploitation,^[3] interdiction, industry relationships, collaboration with other intelligence community entities, and advanced mathematical techniques.

Information about the program's existence was leaked in 2013 by Edward Snowden. Although Snowden's documents do not contain technical information on exact cryptanalytic capabilities because Snowden did not have clearance access to such information,^[4] they do contain a 2010 GCHQ presentation which claims that "vast amounts of encrypted Internet data which have up till now been discarded are now exploitable".^[1] A number of technical details regarding the program found in Snowden's documents were additionally censored by the press at the behest of US intelligence officials.^[5] Out of all the programs that have been leaked by Snowden, the Bullrun Decryption Program is by far the most expensive. Snowden claims that since 2011, expenses devoted to Bullrun amount to $800 million. The leaked documents reveal that Bullrun seeks to "defeat the encryption used in specific network communication technologies".^[6]