CVE-2020-25647
Published: 2 March 2021
A flaw was found in grub2 in versions prior to 2.06. During USB device initialization, descriptors are read with very little bounds checking and assumes the USB device is providing sane values. If properly exploited, an attacker could trigger memory corruption leading to arbitrary code execution allowing a bypass of the Secure Boot mechanism. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Notes
| Author | Note |
|---|---|
| sbeattie | Ubuntu packaging does not include the usb module in the signed EFI grub artifacts, so is not affected. grub2-unsigned will contain fixes and supersede grub2, which will contain only BIOS grub bits. |
Priority
Status
| Package | Release | Status |
|---|---|---|
|
grub2 Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(usb not allowed in secure boot)
|
| focal |
Not vulnerable
(usb not allowed in secure boot)
|
|
| groovy |
Not vulnerable
(usb not allowed in secure boot)
|
|
| hirsute |
Not vulnerable
(usb not allowed in secure boot)
|
|
| impish |
Not vulnerable
(usb not allowed in secure boot)
|
|
| jammy |
Not vulnerable
(usb not allowed in secure boot)
|
|
| trusty |
Not vulnerable
(usb not allowed in secure boot)
|
|
| upstream |
Needs triage
|
|
| xenial |
Not vulnerable
(usb not allowed in secure boot)
|
|
|
grub2-signed Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(usb not allowed in secure boot)
|
| focal |
Not vulnerable
(usb not allowed in secure boot)
|
|
| groovy |
Not vulnerable
(usb not allowed in secure boot)
|
|
| hirsute |
Not vulnerable
(usb not allowed in secure boot)
|
|
| impish |
Not vulnerable
(usb not allowed in secure boot)
|
|
| jammy |
Not vulnerable
(usb not allowed in secure boot)
|
|
| trusty |
Not vulnerable
(usb not allowed in secure boot)
|
|
| upstream |
Needs triage
|
|
| xenial |
Not vulnerable
(usb not allowed in secure boot)
|
|
|
grub2-unsigned Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(usb not allowed in secure boot)
|
| focal |
Not vulnerable
(usb not allowed in secure boot)
|
|
| groovy |
Not vulnerable
(usb not allowed in secure boot)
|
|
| hirsute |
Not vulnerable
(usb not allowed in secure boot)
|
|
| impish |
Not vulnerable
(usb not allowed in secure boot)
|
|
| jammy |
Not vulnerable
(usb not allowed in secure boot)
|
|
| trusty |
Not vulnerable
(usb not allowed in secure boot)
|
|
| upstream |
Needs triage
|
|
| xenial |
Not vulnerable
(usb not allowed in secure boot)
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.6 |
| Attack vector | Physical |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Changed |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |