A joint US Navy and NSA report, prepared three months after a US spy plane was forced to crash land in China, assesses the degree to which surveillance secrets were compromised: see the Intercept article Burn After Reading: Snowden Documents Reveal Scope of Secrets Exposed to China in 2001 Spy Plane Incident, 10 April 2017.
This joint NSA/GCHQ research paper dated 20 January 2011 cites encryption as a threat impacting on both agencies: see the Intercept article Profiled: From Radio to Porn, British Spies Track Web Users’ Online Identities, 25 September 2015.
This extract from the US intelligence community’s 2013 Congressional Budget Justification shows expenditure on the Analysis of Target Systems project, which aims to defeat the encryption in commercial software and hardware: see the Intercept article iSpy: The CIA Campaign to Steal Apple’s Secrets, 10 March 2015.
This internal NSA wiki page from 2012 invites employees to the annual CIA Engineering Development Group “Jamboree” for discussing advancements in the compromise of consumer hardware and software: see the Intercept article iSpy: The CIA Campaign to Steal Apple’s Secrets, 10 March 2015.
This NSA memo summarises a talk given by Roger Dingledine of the Tor Project on 1 November 2007: see the Secret NSA documents show campaign against Tor encrypted network, 4 October 2013.