Variable Time Tag Comparison on SimpleLink™ Devices

TI-PSIRT-2019-080030

Publication date: June 5, 2020

Summary

The signature verification implementation uses a non-constant time memcmp function, which enables the MAC check to be potentially vulnerable to a timing attack.

CVSS base score: 7.5

CVSS vector: https://www.first.org/cvss/calculator/3.0

Affected products and versions

CC26X0
CC13X0
CC2640R2
CC26X2
CC13X2
MSP432E4
CC32XX

Potentially impacted features

CC26X0, CC13X0: AES CCM
CC26X2, CC13X2: AES CCM, AES GCM, ECDSA, ECJPAKE
MSP432E4: AES CCM, AES GCM
CC32XX: HMAC

Suggested mitigations

The following service pack releases address the potential vulnerability:

Affected SDK	SDK version with mitigation
SimpleLink CC13x2-26x2-SDK	3.30.00.03 and newer
SimpleLink MSP432E4 SDK	3.30.00.22 and newer
SimpleLink CC32xx SDK	3.30.00.04 and newer
SimpleLink CC13x0 SDK	4.10.00.10 and newer
SimpleLink CC2640R2 SDK	4.10.00.10 and newer

Acknowledgment

TI internal finding

Revision history

Version 1.0 initial publication

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