CVE Vulnerabilities

CVE-2014-5045

Improper Link Resolution Before File Access ('Link Following')

Published: Aug 01, 2014 | Modified: Apr 12, 2025
CVSS 3.x
N/A
Source:
NVD
CVSS 2.x
6.2 MEDIUM
AV:L/AC:H/Au:N/C:C/I:C/A:C
RedHat/V2
6.2 MODERATE
AV:L/AC:H/Au:N/C:C/I:C/A:C
RedHat/V3
Ubuntu
MEDIUM
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The mountpoint_last function in fs/namei.c in the Linux kernel before 3.15.8 does not properly maintain a certain reference count during attempts to use the umount system call in conjunction with a symlink, which allows local users to cause a denial of service (memory consumption or use-after-free) or possibly have unspecified other impact via the umount program.

Weakness

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

Affected Software

NameVendorStart VersionEnd Version
Linux_kernelLinux*3.15.8 (excluding)
Red Hat Enterprise Linux 6RedHatkernel-0:2.6.32-504.el6*
Red Hat Enterprise Linux 6.5 Extended Update SupportRedHatkernel-0:2.6.32-431.46.2.el6*
Red Hat Enterprise Linux 7RedHatkernel-0:3.10.0-123.13.1.el7*
LinuxUbuntuesm-infra-legacy/trusty*
LinuxUbuntutrusty*
LinuxUbuntutrusty/esm*
LinuxUbuntuupstream*
Linux-2.6Ubuntuupstream*
Linux-armadaxpUbuntuupstream*
Linux-ec2Ubuntuupstream*
Linux-floUbuntutrusty*
Linux-floUbuntuupstream*
Linux-fsl-imx51Ubuntulucid*
Linux-fsl-imx51Ubuntuupstream*
Linux-goldfishUbuntutrusty*
Linux-goldfishUbuntuupstream*
Linux-grouperUbuntutrusty*
Linux-grouperUbuntuupstream*
Linux-grouperUbuntuutopic*
Linux-linaro-omapUbuntuprecise*
Linux-linaro-omapUbuntuupstream*
Linux-linaro-sharedUbuntuprecise*
Linux-linaro-sharedUbuntuupstream*
Linux-linaro-vexpressUbuntuprecise*
Linux-linaro-vexpressUbuntuupstream*
Linux-lts-quantalUbuntuupstream*
Linux-lts-raringUbuntuupstream*
Linux-lts-saucyUbuntuupstream*
Linux-lts-trustyUbuntuprecise*
Linux-lts-trustyUbuntuupstream*
Linux-lts-utopicUbuntuupstream*
Linux-lts-vividUbuntuupstream*
Linux-maguroUbuntutrusty*
Linux-maguroUbuntuupstream*
Linux-makoUbuntutrusty*
Linux-makoUbuntuupstream*
Linux-mantaUbuntutrusty*
Linux-mantaUbuntuupstream*
Linux-mvl-doveUbuntulucid*
Linux-mvl-doveUbuntuupstream*
Linux-qcm-msmUbuntulucid*
Linux-qcm-msmUbuntuprecise*
Linux-qcm-msmUbuntuupstream*
Linux-raspi2Ubuntuupstream*
Linux-raspi2Ubuntuvivid/ubuntu-core*
Linux-ti-omap4Ubuntuupstream*

Potential Mitigations

  • Follow the principle of least privilege when assigning access rights to entities in a software system.
  • Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

References