Leaky Access Tokens Exposed Amazon Photos of Users

The Amazon Photos app for Android insufficiently protected user access tokens, according to a blog post published on Wednesday. Theoretically, with exposed tokens, an attacker could’ve accessed users’ personal data from a number of different Amazon apps – not just Photos but also, for example, Amazon Drive. They also could have performed a ransomware attack, locking up or permanently deleting photos, documents and more. The findings were first reported to Amazon’s Vulnerability Research Program on November 7th of last year. On December 18th, Amazon announced that the issues had been fully resolved. To authenticate users across various apps within their ecosystem, like other software suite vendors, Amazon uses access tokens. It’s convenient for users, but also, potentially, for attackers. In their report, researchers from Checkmarx described how access tokens naturally leaked through an Amazon application programming interface (API) through “a misconfiguration of the com[.]amazon[.]gallery[.]thor[.]app[.]activity[.]ThorViewActivity component, which is implicitly exported in the app’s manifest file” – manifest files describe critical application information to the Android OS and Google Play store – “thus allowing external applications to access it. Whenever this activity is launched, it triggers an HTTP request that carries a header with the customer’s access token.” In a video explainer, they put it in simpler terms: “You can think of it as the password being sent to other…