CVE-2020-11743
Published: 14 April 2020
An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a denial of service because of a bad error path in GNTTABOP_map_grant. Grant table operations are expected to return 0 for success, and a negative number for errors. Some misplaced brackets cause one error path to return 1 instead of a negative value. The grant table code in Linux treats this condition as success, and proceeds with incorrectly initialised state. A buggy or malicious guest can construct its grant table in such a way that, when a backend domain tries to map a grant, it hits the incorrect error path. This will crash a Linux based dom0 or backend domain.
Notes
| Author | Note |
|---|---|
| mdeslaur | hypervisor packages are in universe. For issues in the hypervisor, add appropriate tags to each section, ex: Tags_xen: universe-binary |
Priority
Status
| Package | Release | Status |
|---|---|---|
|
xen Launchpad, Ubuntu, Debian |
bionic |
Needs triage
|
| hirsute |
Ignored
(end of life)
|
|
| groovy |
Ignored
(end of life)
|
|
| xenial |
Needs triage
|
|
| jammy |
Not vulnerable
(4.11.4-1)
|
|
| kinetic |
Not vulnerable
(4.11.4-1)
|
|
| lunar |
Not vulnerable
(4.11.4-1)
|
|
| eoan |
Ignored
(end of life)
|
|
| focal |
Released
(4.11.3+24-g14b62ab3e5-1ubuntu2.3)
|
|
| impish |
Ignored
(end of life)
|
|
| trusty |
Does not exist
|
|
| upstream |
Needs triage
|
|
| Binaries built from this source package are in Universe and so are supported by the community. | ||
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 5.5 |
| Attack vector | Local |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | None |
| Integrity impact | None |
| Availability impact | High |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |