Researchers have found a major encryption flaw in 100 million Samsung Galaxy phones.
From the abstract:
In this work, we expose the cryptographic design and implementation of Android’s Hardware-Backed Keystore in Samsung’s Galaxy S8, S9, S10, S20, and S21 flagship devices. We reversed-engineered and provide a detailed description of the cryptographic design and code structure, and we unveil severe design flaws. We present an IV reuse attack on AES-GCM that allows an attacker to extract hardware-protected key material, and a downgrade attack that makes even the latest Samsung devices vulnerable to the IV reuse attack. We demonstrate working key extraction attacks on the latest devices. We also show the implications of our attacks on two higher-level cryptographic protocols between the TrustZone and a remote server: we demonstrate a working FIDO2 WebAuthn login bypass and a compromise of Google’s Secure Key Import.
Here are the details:
As we discussed in Section 3, the wrapping key used to encrypt the key blobs (HDK) is derived using a salt value computed by the Keymaster TA. In v15 and v20-s9 blobs, the salt is a deterministic function that depends only on the application ID and application data (and constant strings), which the Normal World client fully controls. This means that for a given application, all key blobs will be encrypted using the same key. As the blobs are encrypted in AES-GCM mode-of-operation, the security of the resulting encryption scheme depends on its IV values never being reused.
Gadzooks. That’s a really embarrassing mistake. GSM needs a new nonce for every encryption. Samsung took a secure cipher mode and implemented it insecurely.
News article.
More Stories
Apple Patches Three Actively Exploited Zero-Days
Bugs were found by Citizen Lab and Google Read More
How To Talk To Your Kids About Identity Theft
Let’s be honest, talking to your kids about identity theft isn’t probably top of your list. There’s a long list...
Snatch ransomware – what you need to know
The FBI and US Cybersecurity and Infrastructure Security Agency (CISA) have issued a joint advisory warning organisations about a ransomware-as-a-service...
UK-US Confirm Agreement for Personal Data Transfers
The agreement, which represents an extension to the EU-US Data Privacy Framework, will enable the free flow of personal data...
Donald Trump Jr’s hacked Twitter account announces his father has died
Donald Trump Jr may not have just inherited his famous father's name. He may also have inherited his bad password...
Smashing Security podcast #340: Heated seats, car privacy, and Graham’s porn video
Do you know what data your car is collecting about you? Do you think it’s right for a car manufacturer...