Gentoo: GLSA-201612-02: DavFS2: Local privilege escalation
Summary
DavFS2 installs "/usr/sbin/mount.davfs" as setuid root. This utility
uses "system()" to call "/sbin/modprobe".
While the call to "modprobe" itself cannot be manipulated, a local
authenticated user can set the "MODPROBE_OPTIONS" environment variable
to pass a user controlled path, allowing the loading of an arbitrary
kernel module.
Resolution
All DavFS2 users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=net-fs/davfs2-1.5.2"
References
[ 1 ] CVE-2013-4362 http://nvd.nist.gov/nvd.cfm?cvename=CVE-2013-4362
Availability
This GLSA and any updates to it are available for viewing at
the Gentoo Security Website:
https://security.gentoo.org/glsa/201612-02
Concerns
Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users' machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at https://bugs.gentoo.org.
![Dist Gentoo](/images/distros/dist-gentoo.png)
Synopsis
A vulnerability in DavFS2 allows local users to gain root privileges.
Background
DavFS2 is a file system driver that allows you to mount a WebDAV server as a local disk drive.
Affected Packages
------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 net-fs/davfs2 < 1.5.2 >= 1.5.2
Impact
===== A local user could gain root privileges.
Workaround
The system administrator should ensure that all modules the
"mount.davfs" utility tries to load are loaded upon system boot before
any local user can call the utility.
An additional defense measure can be implemented by enabling the Linux
kernel module signing feature. This assists in the prevention of
arbitrary modules being loaded.