Détail du CWE-1264

The hardware logic for error handling and security checks can incorrectly forward data before the security check is complete.

Many high-performance on-chip bus protocols and processor data-paths employ separate channels for control and data to increase parallelism and maximize throughput. Bugs in the hardware logic that handle errors and security checks can make it possible for data to be forwarded before the completion of the security checks. If the data can propagate to a location in the hardware observable to an attacker, loss of data confidentiality can occur. 'Meltdown' is a concrete example of how de-synchronization between data and permissions checking logic can violate confidentiality requirements. Data loaded from a page marked as privileged was returned to the cpu regardless of current privilege level for performance reasons. The assumption was that the cpu could later remove all traces of this data during the handling of the illegal memory access exception, but this assumption was proven false as traces of the secret data were not removed from the microarchitectural state.

Modes d'introduction

Architecture and Design : The weakness can be introduced in the data transfer or bus protocol itself or in the implementation.
Implementation

Plateformes applicables

Langue

Class: Not Language-Specific (Undetermined)

Systèmes d’exploitation

Class: Not OS-Specific (Undetermined)

Architectures

Class: Not Architecture-Specific (Undetermined)

Technologies

Class: Not Technology-Specific (Undetermined)

Conséquences courantes

Exemples observés

Mesures d’atténuation potentielles

Phases : Architecture and Design

Thoroughly verify the data routing logic to ensure that any error handling or security checks effectively block illegal dataflows.

Notes de cartographie des vulnérabilités

Justification : This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Commentaire : Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

Modèles d'attaque associés

NotesNotes

As of CWE 4.9, members of the CWE Hardware SIG are closely analyzing this entry and others to improve CWE's coverage of transient execution weaknesses, which include issues related to Spectre, Meltdown, and other attacks. Additional investigation may include other weaknesses related to microarchitectural state. As a result, this entry might change significantly in CWE 4.10.

Soumission

Modifications