CVE-2015-2752
Description
From CVE.org
The XEN_DOMCTL_memory_mapping hypercall in Xen 3.2.x through 4.5.x, when using a PCI passthrough device, is not preemptible, which allows local x86 HVM domain users to cause a denial of service (host CPU consumption) via a crafted request to the device model (qemu-dm).
Statement
This issue dos affect the kernel-xen packages as shipped with Red Hat Enterprise Linux 5.
Red Hat Enterprise Linux 5 is now in Production 3 Phase of the support and maintenance life cycle. This has been rated as having Moderate security impact and is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v2 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.3 | 4.9 | N/A |
| Attack Vector | Adjacent Network | Local | N/A |
| Access Complexity | High | Low | N/A |
| Authentication | Single | None | N/A |
| Confidentiality Impact | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | Complete | Complete | N/A |
Vector
Red Hat: AV:A/AC:H/Au:S/C:N/I:N/A:C
NVD: AV:L/AC:L/Au:N/C:N/I:N/A:C
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
If an attacker can trigger the allocation of the limited resources, but the number or size of the resources is not controlled, then the most common result is denial of service. This would prevent valid users from accessing the product, and it could potentially have an impact on the surrounding environment, i.e., the product may slow down, crash due to unhandled errors, or lock out legitimate users. For example, a memory exhaustion attack against an application could slow down the application as well as its host operating system.
Access Control,Other
Technical Impact: Bypass Protection Mechanism; Other
In some cases it may be possible to force the product to "fail open" in the event of resource exhaustion. The state of the product -- and possibly the security functionality - may then be compromised.
Acknowledgements
Red Hat would like to thank Xen for reporting this issue.
Frequently Asked Questions
Not sure what something means? Check out our Security Glossary.
Want to get errata notifications? Sign up here.
