6.4 Medium
CVSS3
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
0.0004 Low
EPSS
Percentile
5.1%
A flaw was found in tpm2-tss, which is an open source software implementation of the Trusted Computing Group (TCG) Trusted Platform Module (TPM) 2 Software Stack (TSS2). In affected versions, Tss2_RC_SetHandler
and Tss2_RC_Decode
index into the layer_handler
with an 8-bit layer number, but the array only has TPM2_ERROR_TSS2_RC_LAYER_COUNT
entries. Trying to add a handler for higher-numbered layers or to decode a response code with a layer number, reads/writes past the end of the buffer. This buffer overrun could result in arbitrary code execution. An example attack is a man-in-the-middle (MiTM) bus attack that returns 0xFFFFFFFFFF for the RC. Given the common use case of TPM modules, an attacker must have local access to the target machine with local system privileges, which allows access to the TPM system. Usually, TPM access requires administrative privileges.