Das U-Boot cryptographic issue

Summaryinfo

A vulnerability, which was classified as critical, has been found in Das U-Boot. This issue affects some unknown processing. This manipulation causes cryptographic issue. This vulnerability is tracked as CVE-2017-3226. It is feasible to perform the attack on the physical device. No exploit exists.

Detailsinfo

A vulnerability was found in Das U-Boot (affected version unknown). It has been declared as critical. Affected by this vulnerability is an unknown functionality. The manipulation with an unknown input leads to a cryptographic issue vulnerability. The CWE definition for the vulnerability is CWE-310. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

The bug was discovered 09/08/2017. The weakness was disclosed 07/24/2018 by Xavier as confirmed advisory (CERT.org). The advisory is shared at kb.cert.org. This vulnerability is known as CVE-2017-3226 since 12/04/2016. An attack has to be approached locally. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1600 for this issue.

The vulnerability was handled as a non-public zero-day exploit for at least 319 days. During that time the estimated underground price was around $0-$5k.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 100675†). The entry VDB-122136 is pretty similar. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• Das U-Boot

License

• free

CPE 2.3info

• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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