CVE-2019-20908 Information

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.

CVSS Vector

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

Reference

http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00009.html http://www.openwall.com/lists/oss-security/2020/07/20/6 http://www.openwall.com/lists/oss-security/2020/07/29/3 http://www.openwall.com/lists/oss-security/2020/07/30/2 http://www.openwall.com/lists/oss-security/2020/07/30/3 https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1957a85b0032a81e6482ca4aab883643b8dae06e https://git.zx2c4.com/american-unsigned-language/tree/american-unsigned-language.sh https://mailarchives.bentasker.co.uk/Mirrors/OSSSec/2020/06-Jun/msg00035.html https://usn.ubuntu.com/4426-1/ https://usn.ubuntu.com/4427-1/ https://usn.ubuntu.com/4439-1/ https://usn.ubuntu.com/4440-1/

Attack Complexity

LOW

Privileges Required

HIGH

User Interaction Required

HIGH

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

6.7