CVE Vulnerabilities

CVE-2012-4508

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

Published: Dec 21, 2012 | Modified: Jan 08, 2014
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
1.9 LOW
AV:L/AC:M/Au:N/C:P/I:N/A:N
RedHat/V2
4.9 IMPORTANT
AV:L/AC:L/Au:N/C:C/I:N/A:N
RedHat/V3
Ubuntu

Race condition in fs/ext4/extents.c in the Linux kernel before 3.4.16 allows local users to obtain sensitive information from a deleted file by reading an extent that was not properly marked as uninitialized.

Weakness

The program contains a code sequence that can run concurrently with other code, and the code sequence 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 that is operating concurrently.

Affected Software

Name Vendor Start Version End Version
Linux_kernel Linux 3.0 3.0
Linux_kernel Linux 3.0 3.0
Linux_kernel Linux 3.0 3.0
Linux_kernel Linux 3.0 3.0
Linux_kernel Linux 3.0 3.0
Linux_kernel Linux 3.0 3.0
Linux_kernel Linux 3.0 3.0
Linux_kernel Linux 3.0.1 3.0.1
Linux_kernel Linux 3.0.2 3.0.2
Linux_kernel Linux 3.0.3 3.0.3
Linux_kernel Linux 3.0.4 3.0.4
Linux_kernel Linux 3.0.5 3.0.5
Linux_kernel Linux 3.0.6 3.0.6
Linux_kernel Linux 3.0.7 3.0.7
Linux_kernel Linux 3.0.8 3.0.8
Linux_kernel Linux 3.0.9 3.0.9
Linux_kernel Linux 3.0.10 3.0.10
Linux_kernel Linux 3.0.11 3.0.11
Linux_kernel Linux 3.0.12 3.0.12
Linux_kernel Linux 3.0.13 3.0.13
Linux_kernel Linux 3.0.14 3.0.14
Linux_kernel Linux 3.0.15 3.0.15
Linux_kernel Linux 3.0.16 3.0.16
Linux_kernel Linux 3.0.17 3.0.17
Linux_kernel Linux 3.0.18 3.0.18
Linux_kernel Linux 3.0.19 3.0.19
Linux_kernel Linux 3.0.20 3.0.20
Linux_kernel Linux 3.0.21 3.0.21
Linux_kernel Linux 3.0.22 3.0.22
Linux_kernel Linux 3.0.23 3.0.23
Linux_kernel Linux 3.0.24 3.0.24
Linux_kernel Linux 3.0.25 3.0.25
Linux_kernel Linux 3.0.26 3.0.26
Linux_kernel Linux 3.0.27 3.0.27
Linux_kernel Linux 3.0.28 3.0.28
Linux_kernel Linux 3.0.29 3.0.29
Linux_kernel Linux 3.0.30 3.0.30
Linux_kernel Linux 3.0.31 3.0.31
Linux_kernel Linux 3.0.32 3.0.32
Linux_kernel Linux 3.0.33 3.0.33
Linux_kernel Linux 3.0.34 3.0.34
Linux_kernel Linux 3.0.35 3.0.35
Linux_kernel Linux 3.0.36 3.0.36
Linux_kernel Linux 3.0.37 3.0.37
Linux_kernel Linux 3.0.38 3.0.38
Linux_kernel Linux 3.0.39 3.0.39
Linux_kernel Linux 3.0.40 3.0.40
Linux_kernel Linux 3.0.41 3.0.41
Linux_kernel Linux 3.0.42 3.0.42
Linux_kernel Linux 3.0.43 3.0.43
Linux_kernel Linux 3.0.44 3.0.44
Linux_kernel Linux 3.1 3.1
Linux_kernel Linux 3.1 3.1
Linux_kernel Linux 3.1 3.1
Linux_kernel Linux 3.1 3.1
Linux_kernel Linux 3.1 3.1
Linux_kernel Linux 3.1.1 3.1.1
Linux_kernel Linux 3.1.2 3.1.2
Linux_kernel Linux 3.1.3 3.1.3
Linux_kernel Linux 3.1.4 3.1.4
Linux_kernel Linux 3.1.5 3.1.5
Linux_kernel Linux 3.1.6 3.1.6
Linux_kernel Linux 3.1.7 3.1.7
Linux_kernel Linux 3.1.8 3.1.8
Linux_kernel Linux 3.1.9 3.1.9
Linux_kernel Linux 3.1.10 3.1.10
Linux_kernel Linux 3.2 3.2
Linux_kernel Linux 3.2 3.2
Linux_kernel Linux 3.2 3.2
Linux_kernel Linux 3.2 3.2
Linux_kernel Linux 3.2 3.2
Linux_kernel Linux 3.2 3.2
Linux_kernel Linux 3.2 3.2
Linux_kernel Linux 3.2 3.2
Linux_kernel Linux 3.2.1 3.2.1
Linux_kernel Linux 3.2.1 3.2.1
Linux_kernel Linux 3.2.2 3.2.2
Linux_kernel Linux 3.2.3 3.2.3
Linux_kernel Linux 3.2.4 3.2.4
Linux_kernel Linux 3.2.5 3.2.5
Linux_kernel Linux 3.2.6 3.2.6
Linux_kernel Linux 3.2.7 3.2.7
Linux_kernel Linux 3.2.8 3.2.8
Linux_kernel Linux 3.2.9 3.2.9
Linux_kernel Linux 3.2.10 3.2.10
Linux_kernel Linux 3.2.11 3.2.11
Linux_kernel Linux 3.2.12 3.2.12
Linux_kernel Linux 3.2.13 3.2.13
Linux_kernel Linux 3.2.14 3.2.14
Linux_kernel Linux 3.2.15 3.2.15
Linux_kernel Linux 3.2.16 3.2.16
Linux_kernel Linux 3.2.17 3.2.17
Linux_kernel Linux 3.2.18 3.2.18
Linux_kernel Linux 3.2.19 3.2.19
Linux_kernel Linux 3.2.20 3.2.20
Linux_kernel Linux 3.2.21 3.2.21
Linux_kernel Linux 3.2.22 3.2.22
Linux_kernel Linux 3.2.23 3.2.23
Linux_kernel Linux 3.2.24 3.2.24
Linux_kernel Linux 3.2.25 3.2.25
Linux_kernel Linux 3.2.26 3.2.26
Linux_kernel Linux 3.2.27 3.2.27
Linux_kernel Linux 3.2.28 3.2.28
Linux_kernel Linux 3.2.29 3.2.29
Linux_kernel Linux 3.2.30 3.2.30
Linux_kernel Linux 3.3 3.3
Linux_kernel Linux 3.3 3.3
Linux_kernel Linux 3.3 3.3
Linux_kernel Linux 3.3 3.3
Linux_kernel Linux 3.3 3.3
Linux_kernel Linux 3.3 3.3
Linux_kernel Linux 3.3 3.3
Linux_kernel Linux 3.3 3.3
Linux_kernel Linux 3.3.1 3.3.1
Linux_kernel Linux 3.3.2 3.3.2
Linux_kernel Linux 3.3.3 3.3.3
Linux_kernel Linux 3.3.4 3.3.4
Linux_kernel Linux 3.3.5 3.3.5
Linux_kernel Linux 3.3.6 3.3.6
Linux_kernel Linux 3.3.7 3.3.7
Linux_kernel Linux 3.3.8 3.3.8
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4 3.4
Linux_kernel Linux 3.4.1 3.4.1
Linux_kernel Linux 3.4.1 3.4.1
Linux_kernel Linux 3.4.2 3.4.2
Linux_kernel Linux 3.4.2 3.4.2
Linux_kernel Linux 3.4.3 3.4.3
Linux_kernel Linux 3.4.3 3.4.3
Linux_kernel Linux 3.4.4 3.4.4
Linux_kernel Linux 3.4.4 3.4.4
Linux_kernel Linux 3.4.5 3.4.5
Linux_kernel Linux 3.4.5 3.4.5
Linux_kernel Linux 3.4.10 3.4.10
Linux_kernel Linux 3.4.11 3.4.11
Linux_kernel Linux 3.4.12 3.4.12
Linux_kernel Linux 3.4.13 3.4.13
Linux_kernel Linux 3.4.14 3.4.14
Linux_kernel Linux * 3.4.15
Red Hat Enterprise Linux 5 RedHat kernel-0:2.6.18-308.24.1.el5 *
Red Hat Enterprise Linux 6 RedHat kernel-0:2.6.32-358.el6 *
Red Hat Enterprise Linux 6.2 EUS - Server and Compute Node Only RedHat kernel-0:2.6.32-220.45.1.el6 *
Red Hat Enterprise Linux 6.3 EUS - Server and Compute Node Only RedHat kernel-0:2.6.32-279.39.1.el6 *
Red Hat Enterprise MRG 2 RedHat kernel-rt-0:3.2.33-rt50.66.el6rt *
Linux Ubuntu hardy *
Linux Ubuntu lucid *
Linux Ubuntu natty *
Linux Ubuntu oneiric *
Linux Ubuntu precise *
Linux Ubuntu precise/esm *
Linux Ubuntu quantal *
Linux Ubuntu upstream *
Linux-armadaxp Ubuntu precise *
Linux-armadaxp Ubuntu quantal *
Linux-armadaxp Ubuntu upstream *
Linux-aws Ubuntu upstream *
Linux-ec2 Ubuntu lucid *
Linux-ec2 Ubuntu upstream *
Linux-flo Ubuntu trusty *
Linux-flo Ubuntu upstream *
Linux-flo Ubuntu utopic *
Linux-flo Ubuntu vivid *
Linux-flo Ubuntu vivid/stable-phone-overlay *
Linux-flo Ubuntu wily *
Linux-flo Ubuntu xenial *
Linux-flo Ubuntu yakkety *
Linux-fsl-imx51 Ubuntu lucid *
Linux-fsl-imx51 Ubuntu upstream *
Linux-gke Ubuntu upstream *
Linux-goldfish Ubuntu saucy *
Linux-goldfish Ubuntu trusty *
Linux-goldfish Ubuntu upstream *
Linux-grouper Ubuntu saucy *
Linux-grouper Ubuntu trusty *
Linux-grouper Ubuntu upstream *
Linux-grouper Ubuntu utopic *
Linux-hwe Ubuntu upstream *
Linux-hwe-edge Ubuntu upstream *
Linux-linaro-omap Ubuntu natty *
Linux-linaro-omap Ubuntu oneiric *
Linux-linaro-omap Ubuntu precise *
Linux-linaro-omap Ubuntu quantal *
Linux-linaro-omap Ubuntu upstream *
Linux-linaro-shared Ubuntu oneiric *
Linux-linaro-shared Ubuntu precise *
Linux-linaro-shared Ubuntu quantal *
Linux-linaro-shared Ubuntu upstream *
Linux-linaro-vexpress Ubuntu natty *
Linux-linaro-vexpress Ubuntu oneiric *
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-backport-natty Ubuntu lucid *
Linux-lts-backport-natty Ubuntu upstream *
Linux-lts-backport-oneiric Ubuntu lucid *
Linux-lts-backport-oneiric Ubuntu upstream *
Linux-lts-quantal Ubuntu precise *
Linux-lts-quantal Ubuntu upstream *
Linux-lts-raring Ubuntu upstream *
Linux-lts-trusty Ubuntu upstream *
Linux-lts-utopic Ubuntu upstream *
Linux-lts-vivid Ubuntu upstream *
Linux-lts-wily Ubuntu upstream *
Linux-lts-xenial Ubuntu upstream *
Linux-maguro Ubuntu saucy *
Linux-maguro Ubuntu trusty *
Linux-maguro Ubuntu upstream *
Linux-mako Ubuntu saucy *
Linux-mako Ubuntu trusty *
Linux-mako Ubuntu upstream *
Linux-mako Ubuntu utopic *
Linux-mako Ubuntu vivid *
Linux-mako Ubuntu vivid/stable-phone-overlay *
Linux-mako Ubuntu wily *
Linux-mako Ubuntu xenial *
Linux-mako Ubuntu yakkety *
Linux-manta Ubuntu saucy *
Linux-manta Ubuntu upstream *
Linux-mvl-dove Ubuntu lucid *
Linux-mvl-dove Ubuntu upstream *
Linux-qcm-msm Ubuntu lucid *
Linux-qcm-msm Ubuntu natty *
Linux-qcm-msm Ubuntu oneiric *
Linux-qcm-msm Ubuntu precise *
Linux-qcm-msm Ubuntu quantal *
Linux-qcm-msm Ubuntu upstream *
Linux-raspi2 Ubuntu upstream *
Linux-raspi2 Ubuntu vivid/ubuntu-core *
Linux-snapdragon Ubuntu upstream *
Linux-ti-omap4 Ubuntu natty *
Linux-ti-omap4 Ubuntu oneiric *
Linux-ti-omap4 Ubuntu precise *
Linux-ti-omap4 Ubuntu quantal *
Linux-ti-omap4 Ubuntu upstream *

Extended Description

This can have security implications when the expected synchronization is in security-critical code, such as recording whether a user is authenticated or modifying important state information that should not be influenced by an outsider. A race condition occurs within concurrent environments, and 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. Programmers may assume that certain code sequences execute too quickly to be affected by an interfering code sequence; when they are not, this violates atomicity. For example, the single “x++” statement may appear atomic at the code layer, but it is actually non-atomic at the instruction layer, since it involves a read (the original value of x), followed by a computation (x+1), followed by a write (save the result to x). The interfering code sequence could be “trusted” or “untrusted.” A trusted interfering code sequence occurs within the program; 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 program.

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