The x86_emulate function in arch/x86/x86_emulate/x86_emulate.c in Xen 4.4.x and earlier does not properly check supervisor mode permissions, which allows local HVM users to cause a denial of service (guest crash) or gain guest kernel mode privileges via vectors involving an (1) HLT, (2) LGDT, (3) LIDT, or (4) LMSW instruction.
The MITRE CVE dictionary describes this issue as:
Find out more about CVE-2014-7155 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 | 6.2 |
|---|---|
| Base Metrics | AV:L/AC:H/Au:N/C:C/I:C/A:C |
| Access Vector | Local |
| Access Complexity | High |
| Authentication | None |
| Confidentiality Impact | Complete |
| Integrity Impact | Complete |
| 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