This attack targets a race condition occurring when multiple processes
access and manipulate the same resource concurrently and the outcome of the
execution depends on the particular order in which the access takes place.
The attacker can leverage a race condition by "running the race", modifying
the resource and modifying the normal execution flow. For instance a race
condition can occur while accessing a file, the attacker can trick the
system by replacing the original file with his version and cause the system
to read the malicious file.
Attack Execution Flow
The attacker explores to gauge what level of
access he has.
The attacker gains access to a resource on the
target host. The attacker modifies the targeted
resource. The resource's value is used to determine
the next normal execution action.
The resource is modified/checked concurrently by
multiple processes. By using one of the processes,
the attacker is able to modify the value just before
it is consumed by a different process. A race
condition occurs and is exploited by the Attacker to
abuse the target host.
Attack Prerequisites
A resource is accessed/modified concurrently by multiple processes such
that a race condition exists.
The attacker has the ability to modify the resource.
Typical Likelihood of Exploit
Likelihood: High
Methods of Attack
Time and State
Modification of Resources
Examples-Instances
Description
The Net Direct client for Linux before 6.0.5 in Nortel Application
Switch 2424, VPN 3050 and 3070, and SSL VPN Module 1000 extracts and
executes files with insecure permissions, which allows local users to
exploit a race condition to replace a world-writable file in
/tmp/NetClient and cause another user to execute arbitrary code when
attempting to execute this client, as demonstrated by replacing
/tmp/NetClient/client.
Related Vulnerabilities
CVE-2007-1057
Description
The following code illustrates a file that is accessed multiple times
by name in a publicly accessible directory. A race condition exists
between the accesses where an attacker can replace the file referenced
by the name.
Description
