CVE-2020-24455

Description

The tpm2-tss package introduced an implementation of TCG Feature API (FAPI) from v2.4.0. While instantiating TPM policy via FAPI, TPM's Platform Configuration Register (PCR) are used to compute policy digest. While reading PCR values via 'ifapi_read_pcr' routine, a PCR list counter was not set which can lead to an incorrect policy instantiation. This may potentially lead to a DoS scenario.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score4.16.7N/A
Attack VectorLocalLocalN/A
Attack ComplexityHighLowN/A
Privileges RequiredHighHighN/A
User InteractionNoneNoneN/A
ScopeUnchangedUnchangedN/A
ConfidentialityNoneHighN/A
Integrity ImpactNoneHighN/A
Availability ImpactHighHighN/A

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H

NVD: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Understanding the Weakness (CWE)

Integrity,Other

Technical Impact: Unexpected State; Quality Degradation; Varies by Context

The uninitialized data may be invalid, causing logic errors within the program. In some cases, this could result in a security problem.

Frequently Asked Questions

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