CVE Vulnerabilities

CVE-2013-1935

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Published: Jul 16, 2013 | Modified: Apr 11, 2025
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
5.7 MEDIUM
AV:A/AC:M/Au:N/C:N/I:N/A:C
RedHat/V2
5.7 IMPORTANT
AV:A/AC:M/Au:N/C:N/I:N/A:C
RedHat/V3
Ubuntu
MEDIUM

A certain Red Hat patch to the KVM subsystem in the kernel package before 2.6.32-358.11.1.el6 on Red Hat Enterprise Linux (RHEL) 6 does not properly implement the PV EOI feature, which allows guest OS users to cause a denial of service (host OS crash) by leveraging a time window during which interrupts are disabled but copy_to_user function calls are possible.

Weakness

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.

Affected Software

Name Vendor Start Version End Version
Enterprise_linux Redhat 6.0 (including) 6.0 (including)
Red Hat Enterprise Linux 6 RedHat kernel-0:2.6.32-358.11.1.el6 *
RHEV 3.X Hypervisor and Agents for RHEL-6 RedHat rhev-hypervisor6-0:6.4-20130528.0.el6_4 *
Linux Ubuntu upstream *
Linux-armadaxp Ubuntu upstream *
Linux-ec2 Ubuntu upstream *
Linux-fsl-imx51 Ubuntu lucid *
Linux-fsl-imx51 Ubuntu upstream *
Linux-linaro-omap Ubuntu precise *
Linux-linaro-omap Ubuntu quantal *
Linux-linaro-omap Ubuntu upstream *
Linux-linaro-shared Ubuntu precise *
Linux-linaro-shared Ubuntu quantal *
Linux-linaro-shared Ubuntu upstream *
Linux-linaro-vexpress Ubuntu precise *
Linux-linaro-vexpress Ubuntu quantal *
Linux-linaro-vexpress Ubuntu upstream *
Linux-lts-backport-maverick Ubuntu lucid *
Linux-lts-backport-maverick Ubuntu upstream *
Linux-lts-quantal Ubuntu upstream *
Linux-lts-raring Ubuntu upstream *
Linux-mvl-dove Ubuntu lucid *
Linux-mvl-dove Ubuntu upstream *
Linux-qcm-msm Ubuntu lucid *
Linux-qcm-msm Ubuntu precise *
Linux-qcm-msm Ubuntu quantal *
Linux-qcm-msm Ubuntu upstream *
Linux-ti-omap4 Ubuntu upstream *

Extended Description

A race condition occurs within concurrent environments, and it is effectively a property of a code sequence. Depending on the context, a code sequence may be in the form of a function call, a small number of instructions, a series of program invocations, etc. A race condition violates these properties, which are closely related:

A race condition exists when an “interfering code sequence” can still access the shared resource, violating exclusivity. The interfering code sequence could be “trusted” or “untrusted.” A trusted interfering code sequence occurs within the product; it cannot be modified by the attacker, and it can only be invoked indirectly. An untrusted interfering code sequence can be authored directly by the attacker, and typically it is external to the vulnerable product.

Potential Mitigations

  • Minimize the usage of shared resources in order to remove as much complexity as possible from the control flow and to reduce the likelihood of unexpected conditions occurring.
  • Additionally, this will minimize the amount of synchronization necessary and may even help to reduce the likelihood of a denial of service where an attacker may be able to repeatedly trigger a critical section (CWE-400).

References