CVE-2019-20908

Name: CVE-2019-20908
Creator: NVD / NIST
Published: 2020-07-15T22:15:13.78+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.7/10EPSS 0.51%

Last modified Jun 17, 2026

CVE-2019-20908 is a medium-severity vulnerability rated 6.7/10 on the CVSS scale. An issue was discovered in drivers/firmware/efi/efi.c in the Linux kernel before 5.4. Incorrect access permissions for the efivar_ssdt ACPI variable could be used by attackers to bypass lockdown or secure boot restrictions, aka CID-1957a85b0032.. EPSS estimates a 0.51% chance of exploitation in the next 30 days.

Description

An issue was discovered in drivers/firmware/efi/efi.c in the Linux kernel before 5.4. Incorrect access permissions for the efivar_ssdt ACPI variable could be used by attackers to bypass lockdown or secure boot restrictions, aka CID-1957a85b0032.

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

0.51%

39.8th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	< 5.4
Opensuse	Leap	15.1
Canonical	Ubuntu Linux	16.04
Canonical	Ubuntu Linux	18.04

References

http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00009.htmlMailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/07/20/6Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/07/29/3Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/07/30/2Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/07/30/3Mailing List, Third Party Advisory
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4Release Notes, Vendor Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1957a85b0032a81e6482ca4aab883643b8dae06ePatch, Vendor Advisory
https://git.zx2c4.com/american-unsigned-language/tree/american-unsigned-language.shPatch, Third Party Advisory
https://mailarchives.bentasker.co.uk/Mirrors/OSSSec/2020/06-Jun/msg00035.htmlMailing List, Third Party Advisory
https://usn.ubuntu.com/4426-1/Third Party Advisory
https://usn.ubuntu.com/4427-1/Third Party Advisory
https://usn.ubuntu.com/4439-1/Third Party Advisory
https://usn.ubuntu.com/4440-1/Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00009.htmlMailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/07/20/6Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/07/29/3Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/07/30/2Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/07/30/3Mailing List, Third Party Advisory
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4Release Notes, Vendor Advisory
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1957a85b0032a81e6482ca4aab883643b8dae06ePatch, Vendor Advisory
https://git.zx2c4.com/american-unsigned-language/tree/american-unsigned-language.shPatch, Third Party Advisory
https://mailarchives.bentasker.co.uk/Mirrors/OSSSec/2020/06-Jun/msg00035.htmlMailing List, Third Party Advisory
https://usn.ubuntu.com/4426-1/Third Party Advisory
https://usn.ubuntu.com/4427-1/Third Party Advisory
https://usn.ubuntu.com/4439-1/Third Party Advisory
https://usn.ubuntu.com/4440-1/Third Party Advisory

Timeline

Published: Jul 15, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-20908?

How severe is CVE-2019-20908?

CVE-2019-20908 has a CVSS score of 6.7/10 (MEDIUM severity). The EPSS model estimates a 0.51% probability of exploitation in the next 30 days.

How do I fix CVE-2019-20908?

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-2019-20908?

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

Scan your code now

Source: NVD / NIST