CVE-2019-20908
Published: 15 July 2020
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.
From the Ubuntu Security Team
Jason A. Donenfeld discovered that the ACPI implementation in the Linux kernel did not properly restrict loading SSDT code from an EFI variable. A privileged attacker could use this to bypass Secure Boot lockdown restrictions and execute arbitrary code in the kernel.
Priority
Status
| Package | Release | Status |
|---|---|---|
|
linux Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-112.113)
|
| eoan |
Ignored
(reached end-of-life)
|
|
| focal |
Not vulnerable
(5.4.0-9.12)
|
|
| groovy |
Not vulnerable
(5.4.0-26.30)
|
|
| precise |
Not vulnerable
(3.0.0-12.20)
|
|
| trusty |
Not vulnerable
(3.11.0-12.19)
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Not vulnerable
(4.2.0-16.19)
|
|
|
Patches: Introduced by 475fb4e8b2f4444d1d7b406ff3a7d21bc89a1e6f |
||
|
linux-aws Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1079.83)
|
| eoan |
Ignored
(reached end-of-life)
|
|
| focal |
Not vulnerable
(5.4.0-1005.5)
|
|
| groovy |
Not vulnerable
(5.4.0-1009.9)
|
|
| precise |
Does not exist
|
|
| trusty |
Not vulnerable
(4.4.0-1002.2)
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Not vulnerable
(4.4.0-1001.10)
|
|
|
linux-aws-5.0 Launchpad, Ubuntu, Debian |
bionic |
Ignored
(was needs-triage now end-of-life)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-aws-5.3 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.3.0-1032.34~18.04.2)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-aws-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-1018.18~18.04.1)
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-aws-hwe Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Released
(4.15.0-1079.83~16.04.1)
|
|
|
linux-azure Launchpad, Ubuntu, Debian |
bionic |
Ignored
(was needs-triage now end-of-life)
|
| eoan |
Ignored
(reached end-of-life)
|
|
| focal |
Not vulnerable
(5.4.0-1006.6)
|
|
| groovy |
Not vulnerable
(5.4.0-1010.10)
|
|
| precise |
Does not exist
|
|
| trusty |
Released
(4.15.0-1092.102~14.04.1)
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Released
(4.15.0-1092.102~16.04.1)
|
|
|
linux-azure-4.15 Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1092.102)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-azure-5.3 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.3.0-1034.35~18.04.1)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-azure-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-1020.20~18.04.1)
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-azure-edge Launchpad, Ubuntu, Debian |
bionic |
Ignored
(was needs-triage now end-of-life)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-dell300x Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(4.15.0-1005.8)
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gcp Launchpad, Ubuntu, Debian |
bionic |
Ignored
(was needs-triage now end-of-life)
|
| eoan |
Ignored
(reached end-of-life)
|
|
| focal |
Not vulnerable
(5.4.0-1005.5)
|
|
| groovy |
Not vulnerable
(5.4.0-1009.9)
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Released
(4.15.0-1080.90~16.04.1)
|
|
|
linux-gcp-4.15 Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1080.90)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gcp-5.3 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.3.0-1032.34~18.04.1)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gcp-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-1019.19~18.04.2)
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gcp-edge Launchpad, Ubuntu, Debian |
bionic |
Ignored
(was needs-triage now end-of-life)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gke-4.15 Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1066.69)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gke-5.0 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.0.0-1045.46)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gke-5.3 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.3.0-1032.34~18.04.1)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gke-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-1025.25~18.04.1)
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gkeop Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| focal |
Not vulnerable
(5.4.0-1008.9)
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-gkeop-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-1001.1)
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-hwe Launchpad, Ubuntu, Debian |
bionic |
Released
(5.3.0-64.58~18.04.1)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Released
(4.15.0-112.113~16.04.1)
|
|
|
linux-hwe-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-37.41~18.04.1)
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-hwe-5.8 Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| focal |
Not vulnerable
(5.8.0-23.24~20.04.1)
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-hwe-edge Launchpad, Ubuntu, Debian |
bionic |
Ignored
(was needs-triage now end-of-life)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Ignored
(was needs-triage now end-of-life)
|
|
|
linux-kvm Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1071.72)
|
| eoan |
Ignored
(reached end-of-life)
|
|
| focal |
Not vulnerable
(5.4.0-1004.4)
|
|
| groovy |
Not vulnerable
(5.4.0-1009.9)
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Not vulnerable
(4.4.0-1004.9)
|
|
|
linux-lts-trusty Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Not vulnerable
(3.13.0-24.46~precise1)
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-lts-xenial Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Not vulnerable
(4.4.0-13.29~14.04.1)
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-oem Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1093.103)
|
| eoan |
Ignored
(reached end-of-life)
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Ignored
(was needs-triage now end-of-life)
|
|
|
linux-oem-5.10 Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| focal |
Not vulnerable
(5.10.0-1008.9)
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-oem-5.6 Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| eoan |
Does not exist
|
|
| focal |
Not vulnerable
(5.6.0-1007.7)
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-oem-osp1 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.0.0-1065.70)
|
| eoan |
Ignored
(reached end-of-life)
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-oracle Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1050.54)
|
| eoan |
Ignored
(reached end-of-life)
|
|
| focal |
Not vulnerable
(5.4.0-1005.5)
|
|
| groovy |
Not vulnerable
(5.4.0-1009.9)
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Released
(4.15.0-1050.54~16.04.1)
|
|
|
linux-oracle-5.0 Launchpad, Ubuntu, Debian |
bionic |
Ignored
(was needs-triage now end-of-life)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-oracle-5.3 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.3.0-1030.32~18.04.1)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-oracle-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-1019.19~18.04.1)
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-raspi Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| eoan |
Does not exist
|
|
| focal |
Not vulnerable
(5.4.0-1007.7)
|
|
| groovy |
Not vulnerable
(5.4.0-1008.8)
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-raspi-5.4 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(5.4.0-1013.13~18.04.1)
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-raspi2 Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1067.71)
|
| eoan |
Ignored
(reached end-of-life)
|
|
| focal |
Ignored
(was needs-triage now end-of-life)
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Not vulnerable
(4.2.0-1013.19)
|
|
|
linux-raspi2-5.3 Launchpad, Ubuntu, Debian |
bionic |
Released
(5.3.0-1030.32~18.04.2)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-riscv Launchpad, Ubuntu, Debian |
bionic |
Does not exist
|
| eoan |
Does not exist
|
|
| focal |
Not vulnerable
(5.4.0-24.28)
|
|
| groovy |
Not vulnerable
(5.4.0-24.28)
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Does not exist
|
|
|
linux-snapdragon Launchpad, Ubuntu, Debian |
bionic |
Released
(4.15.0-1083.91)
|
| eoan |
Does not exist
|
|
| focal |
Does not exist
|
|
| groovy |
Does not exist
|
|
| precise |
Does not exist
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(5.4~rc1)
|
|
| xenial |
Not vulnerable
(4.4.0-1013.15)
|
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 6.7 |
| Attack vector | Local |
| Attack complexity | Low |
| Privileges required | High |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
References
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-20908
- https://www.openwall.com/lists/oss-security/2020/06/14/1
- 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://ubuntu.com/security/notices/USN-4426-1
- https://ubuntu.com/security/notices/USN-4427-1
- https://ubuntu.com/security/notices/USN-4439-1
- https://ubuntu.com/security/notices/USN-4440-1
- NVD
- Launchpad
- Debian