CVE-2020-27339

Name: CVE-2020-27339
Creator: NVD / NIST
Published: 2021-06-16T16:15:07.897+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.7/10EPSS 0.32%

Last modified Jun 17, 2026

CVE-2020-27339 is a medium-severity vulnerability rated 6.7/10 on the CVSS scale. In the kernel in Insyde InsydeH2O 5.x, certain SMM drivers did not correctly validate the CommBuffer and CommBufferSize parameters, allowing callers to corrupt either the firmware or the OS memory. The fixed versions for this issue in the AhciBusDxe, IdeBusDxe, NvmExpressDxe, SdHostDriverDxe, and SdMmcDeviceDxe drivers are 05.16.25, 05.26.25, 05.35.25, 05.43.25, and 05.51.25 (for Kernel 5.1 through 5.5).. EPSS estimates a 0.32% chance of exploitation in the next 30 days.

Description

In the kernel in Insyde InsydeH2O 5.x, certain SMM drivers did not correctly validate the CommBuffer and CommBufferSize parameters, allowing callers to corrupt either the firmware or the OS memory. The fixed versions for this issue in the AhciBusDxe, IdeBusDxe, NvmExpressDxe, SdHostDriverDxe, and SdMmcDeviceDxe drivers are 05.16.25, 05.26.25, 05.35.25, 05.43.25, and 05.51.25 (for Kernel 5.1 through 5.5).

Metrics

CVSS 3.1

6.7/10

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

EPSS Probability

0.32%

23.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-20

Affected Software

Vendor	Product	Versions
Insyde	Insydeh2o	>= 5.3, < 5.34.44
Insyde	Insydeh2o	>= 5.2, < 5.25.44
Insyde	Insydeh2o	>= 5.1, < 5.16.25
Insyde	Insydeh2o	>= 5.4, < 5.42.44
Insyde	Insydeh2o	>= 5.3, < 5.35.25
Insyde	Insydeh2o	>= 5.2, < 5.26.25
Insyde	Insydeh2o	>= 5.4, < 5.43.25
Siemens	Ruggedcom Apr1808 Firmware	All versions
Siemens	Simatic Field Pg M5 Firmware	All versions
Siemens	Simatic Field Pg M6 Firmware	All versions
Siemens	Simatic Ipc127e Firmware	All versions
Siemens	Simatic Ipc227g Firmware	All versions
Siemens	Simatic Ipc277g Firmware	All versions
Siemens	Simatic Ipc327g Firmware	All versions
Siemens	Simatic Ipc377g Firmware	All versions
Siemens	Simatic Ipc427e Firmware	All versions
Siemens	Simatic Ipc477e Firmware	All versions
Siemens	Simatic Ipc477e Pro Firmware	All versions
Siemens	Simatic Ipc627e Firmware	All versions
Siemens	Simatic Ipc647e Firmware	All versions
Siemens	Simatic Ipc677e Firmware	All versions
Siemens	Simatic Ipc847e Firmware	All versions
Siemens	Simatic Itp1000 Firmware	All versions

References

https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdfThird Party Advisory
https://security.netapp.com/advisory/ntap-20220216-0005/Third Party Advisory
https://www.insyde.com/security-pledge/SA-2021001Vendor Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdfThird Party Advisory
https://security.netapp.com/advisory/ntap-20220216-0005/Third Party Advisory
https://www.insyde.com/security-pledge/SA-2021001Vendor Advisory
https://www.kb.cert.org/vuls/id/796611

Timeline

Published: Jun 16, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-27339?

How severe is CVE-2020-27339?

CVE-2020-27339 has a CVSS score of 6.7/10 (MEDIUM severity). The EPSS model estimates a 0.32% probability of exploitation in the next 30 days.

How do I fix CVE-2020-27339?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-27339?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST