COMMON WEAKNESS ENUMERATIONIncomplete

CWE-1273

Device Unlock Credential Sharing

The credentials necessary for unlocking a device are shared across multiple parties and may expose sensitive information.

Abstraction

Base

Structure

Simple

Likelihood of Exploit

Medium

Understand the problem

What is the problem?

The credentials necessary for unlocking a device are shared across multiple parties and may expose sensitive information.

Extended description

"Unlocking a device" often means activating certain unadvertised debug and manufacturer-specific capabilities of a device using sensitive credentials. Unlocking a device might be necessary for the purpose of troubleshooting device problems. For example, suppose a device contains the ability to dump the content of the full system memory by disabling the memory-protection mechanisms. Since this is a highly security-sensitive capability, this capability is "locked" in the production part. Unless the device gets unlocked by supplying the proper credentials, the debug capabilities are not available. For cases where the chip designer, chip manufacturer (fabricator), and manufacturing and assembly testers are all employed by the same company, the risk of compromise of the credentials is greatly reduced. However, the risk is greater when the chip designer is employed by one company, the chip manufacturer is employed by another company (a foundry), and the assemblers and testers are employed by yet a third company. Since these different companies will need to perform various tests on the device to verify correct device function, they all need to share the unlock key. Unfortunately, the level of secrecy and policy might be quite different at each company, greatly increasing the risk of sensitive credentials being compromised.

Root cause

How and when does the problem arise?

Lifecycle phase

Integration

Lifecycle phase

Manufacturing

Risk

What does successful exploitation lead to?

Modify MemoryRead MemoryModify Files or DirectoriesRead Files or DirectoriesModify Application DataExecute Unauthorized Code or CommandsGain Privileges or Assume IdentityBypass Protection Mechanism

Affected security scopes: Confidentiality, Integrity, Availability, Access Control, Accountability, Authentication, Authorization, Non-Repudiation

Once unlock credentials are compromised, an attacker can use the credentials to unlock the device and gain unauthorized access to the hidden functionalities protected by those credentials.

Defence

How is it prevented and fixed?

Integration

Integration aşaması savunması

Detail
Ensure the unlock credentials are shared with the minimum number of parties and with utmost secrecy. To limit the risk associated with compromised credentials, where possible, the credentials should be part-specific.

Manufacturing

Manufacturing aşaması savunması

Detail
Ensure the unlock credentials are shared with the minimum number of parties and with utmost secrecy. To limit the risk associated with compromised credentials, where possible, the credentials should be part-specific.