CVE-2020-5956: Input Validation

Published Jan 5, 2022
·
Updated

An issue was discovered in SdLegacySmm in Insyde InsydeH2O with kernel 5.1 before 05.15.11, 5.2 before 05.25.11, 5.3 before 05.34.11, and 5.4 before 05.42.11. The software SMI handler allows untrusted external input because it does not verify CommBuffer.

Affected Software

4 affected components
Insyde InsydeH2O>=5.2<5.25.11
Insyde InsydeH2O>=5.1<05.15.11
Insyde InsydeH2O>=5.3<05.34.11
Insyde InsydeH2O>=5.4<05.42.11

Event History

Jan 5, 2022
CVE Published
via MITRE·10:55 PM
Data Sourced
via MITRE·10:55 PM
Description

Frequently Asked Questions

1

What is the severity of CVE-2020-5956?

CVE-2020-5956 is classified as a medium severity vulnerability due to the risk it poses from untrusted external input.

2

How do I fix CVE-2020-5956?

To fix CVE-2020-5956, update InsydeH2O to version 5.1.05.15.11, 5.2.05.25.11, 5.3.05.34.11, or 5.4.05.42.11 or later.

3

What systems are affected by CVE-2020-5956?

CVE-2020-5956 affects InsydeH2O UEFI BIOS versions 5.1 before 05.15.11, 5.2 before 05.25.11, 5.3 before 05.34.11, and 5.4 before 05.42.11.

4

What is the impact of CVE-2020-5956?

The impact of CVE-2020-5956 allows an attacker to exploit the SMI handler due to a lack of verification on CommBuffer input.

5

Who is the vendor for CVE-2020-5956?

The vendor for CVE-2020-5956 is Insyde Software, known for their InsydeH2O UEFI BIOS systems.

Contact

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