The research in this paper leads to the discovery of a series of high-impact security weaknesses, which enable a sandboxed malicious app, approved by the Apple Store, to gain unauthorized access to other apps' sensitive data. More specifically, the researchers found that the inter-app interaction services, including the keychain and WebSocket on OS X and URL Scheme on OS X and iOS, can all be exploited by the malware to steal such confidential information as the passwords for iCloud, email and bank, and the secret token of Evernote.
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Signing Me onto Your Accounts through Facebook and Google: a Traffic-Guided Security Study of Commercially Deployed Sign-Sign-On Web Services. This is the whitepaper where researchers discovered eight flaws with SSO technologies in use by major players.
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