Bluetooth implementations may not sufficiently validate elliptic curve parameters during Diffie-Hellman key exchange.
Overview
Bluetooth firmware or operating system software drivers may not
sufficiently validate elliptic curve parameters used to generate public
keys during a Diffie-Hellman key exchange, which may allow a remote
attacker to obtain the encryption key used by the device.
Description
| CWE-325: Missing Required Cryptographic Step – CVE-2018-5383 Bluetooth utilizes a device pairing mechanism based on elliptic-curve Diffie-Hellman (ECDH) key exchange to allow encrypted communication between devices. The ECDH key pair consists of a private and a public key, and the public keys are exchanged to produce a shared pairing key. The devices must also agree on the elliptic curve parameters being used. Previous work on the “Invalid Curve Attack” showed that the ECDH parameters are not always validated before being used in computing the resulted shared key, which reduces attacker effort to obtain the private key of the device under attack if the implementation does not validate all of the parameters before computing the shared key. In some implementations, the elliptic curve parameters are not all Both Bluetooth low energy (LE) implementations of Secure Connections Since the vulnerability was identified, the Bluetooth SIG has updated |
Impact
| An unauthenticated, remote attacker within range may be able to utilize a man-in-the-middle network position to determine the cryptographic keys used by the device. The attacker can then intercept and decrypt and/or forge and inject device messages. |
Solution
| Apply an update
Both software and firmware updates are expected over the coming weeks. Vendor Information
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