Lucene search

K
redhatRedHatRHSA-2011:1241
HistoryAug 31, 2011 - 12:00 a.m.

(RHSA-2011:1241) Moderate: ecryptfs-utils security update

2011-08-3100:00:00
access.redhat.com
23

EPSS

0.002

Percentile

59.9%

eCryptfs is a stacked, cryptographic file system. It is transparent to the
underlying file system and provides per-file granularity. eCryptfs is
released as a Technology Preview for Red Hat Enterprise Linux 5 and 6.

The setuid mount.ecryptfs_private utility allows users to mount an eCryptfs
file system. This utility can only be run by users in the “ecryptfs” group.

A race condition flaw was found in the way mount.ecryptfs_private checked
the permissions of a requested mount point when mounting an encrypted file
system. A local attacker could possibly use this flaw to escalate their
privileges by mounting over an arbitrary directory. (CVE-2011-1831)

A race condition flaw in umount.ecryptfs_private could allow a local
attacker to unmount an arbitrary file system. (CVE-2011-1832)

It was found that mount.ecryptfs_private did not handle certain errors
correctly when updating the mtab (mounted file systems table) file,
allowing a local attacker to corrupt the mtab file and possibly unmount an
arbitrary file system. (CVE-2011-1834)

An insecure temporary file use flaw was found in the ecryptfs-setup-private
script. A local attacker could use this script to insert their own key that
will subsequently be used by a new user, possibly giving the attacker
access to the user’s encrypted data if existing file permissions allow
access. (CVE-2011-1835)

A race condition flaw in mount.ecryptfs_private could allow a local
attacker to overwrite arbitrary files. (CVE-2011-1837)

A race condition flaw in the way temporary files were accessed in
mount.ecryptfs_private could allow a malicious, local user to make
arbitrary modifications to the mtab file. (CVE-2011-3145)

A race condition flaw was found in the way mount.ecryptfs_private checked
the permissions of the directory to mount. A local attacker could use this
flaw to mount (and then access) a directory they would otherwise not have
access to. Note: The fix for this issue is incomplete until a kernel-space
change is made. Future Red Hat Enterprise Linux 5 and 6 kernel updates
will correct this issue. (CVE-2011-1833)

Red Hat would like to thank the Ubuntu Security Team for reporting these
issues. The Ubuntu Security Team acknowledges Vasiliy Kulikov of Openwall
and Dan Rosenberg as the original reporters of CVE-2011-1831,
CVE-2011-1832, and CVE-2011-1833; Dan Rosenberg and Marc Deslauriers as the
original reporters of CVE-2011-1834; Marc Deslauriers as the original
reporter of CVE-2011-1835; and Vasiliy Kulikov of Openwall as the original
reporter of CVE-2011-1837.

Users of ecryptfs-utils are advised to upgrade to these updated packages,
which contain backported patches to correct these issues.