Das U-Boot's AES-CBC encryption feature improperly handles an error condition and may allow attacks against the underlying cryptographic implementation and allow an attacker to decrypt the data

Vulnerability Description

Das U-Boot is a device bootloader that can read its configuration from an AES encrypted file. Devices that make use of Das U-Boot's AES-CBC encryption feature using environment encryption (i.e., setting the configuration parameter CONFIG_ENV_AES=y) read environment variables from disk as the encrypted disk image is processed. An attacker with physical access to the device can manipulate the encrypted environment data to include a crafted two-byte sequence which triggers an error in environment variable parsing. This error condition is improperly handled by Das U-Boot, resulting in an immediate process termination with a debugging message.

References

• http://www.securityfocus.com/bid/100675
• https://www.kb.cert.org/vuls/id/166743