The x86_emulate function in arch/x86/x86_emulate/x86_emulate.c in Xen 3.3.x through 4.4.x does not check the supervisor mode permissions for instructions that generate software interrupts, which allows local HVM guest users to cause a denial of service (guest crash) via unspecified vectors.
The MITRE CVE dictionary describes this issue as:
Find out more about CVE-2014-7156 from the MITRE CVE dictionary dictionary and NIST NVD.
Not vulnerable.
This issue did not affect the versions of the kernel-xen package as shipped with Red Hat Enterprise Linux 5.
NOTE: The following CVSS v2 metrics and score provided are preliminary and subject to review.
| Base Score | 4.9 |
|---|---|
| Base Metrics | AV:L/AC:L/Au:N/C:N/I:N/A:C |
| Access Vector | Local |
| Access Complexity | Low |
| Authentication | None |
| Confidentiality Impact | None |
| Integrity Impact | None |
| Availability Impact | Complete |
Find out more about Red Hat support for the Common Vulnerability Scoring System (CVSS).
| Platform | Package | State |
|---|---|---|
| Red Hat Enterprise Linux 5 | kernel-xen | Not affected |
Vulmon