CVE-2019-18422
Publication date 31 October 2019
Last updated 26 August 2025
Ubuntu priority
Description
An issue was discovered in Xen through 4.12.x allowing ARM guest OS users to cause a denial of service or gain privileges by leveraging the erroneous enabling of interrupts. Interrupts are unconditionally unmasked in exception handlers. When an exception occurs on an ARM system which is handled without changing processor level, some interrupts are unconditionally enabled during exception entry. So exceptions which occur when interrupts are masked will effectively unmask the interrupts. A malicious guest might contrive to arrange for critical Xen code to run with interrupts erroneously enabled. This could lead to data corruption, denial of service, or possibly even privilege escalation. However a precise attack technique has not been identified.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| xen | 25.10 questing |
Not affected
|
| 24.04 LTS noble |
Not affected
|
|
| 22.04 LTS jammy |
Not affected
|
|
| 20.04 LTS focal |
Not affected
|
|
| 18.04 LTS bionic |
Vulnerable
|
|
| 16.04 LTS xenial |
Vulnerable
|
|
| 14.04 LTS trusty | Not in release |
Notes
mdeslaur
hypervisor packages are in universe
alexmurray
This issue is specific only to ARM platforms - x86 systems are not affected
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
8.8 · High
|
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |