ecryptfs security update

CentOS Errata and Security Advisory CESA-2009:1307

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
5.4. These updated ecryptfs-utils packages have been upgraded to upstream
version 75, which provides a number of bug fixes and enhancements over the
previous version. In addition, these packages provide a graphical program
to help configure and use eCryptfs. To start this program, run the command:

ecryptfs-mount-helper-gui

Important: the syntax of certain eCryptfs mount options has changed. Users
who were previously using the initial Technology Preview release of
ecryptfs-utils are advised to refer to the ecryptfs(7) man page, and to
update any affected mount scripts and /etc/fstab entries for eCryptfs file
systems.

A disclosure flaw was found in the way the “ecryptfs-setup-private” script
passed passphrases to the “ecryptfs-wrap-passphrase” and
“ecryptfs-add-passphrase” commands as command line arguments. A local user
could obtain the passphrases of other users who were running the script
from the process listing. (CVE-2008-5188)

These updated packages provide various enhancements, including a mount
helper and supporting libraries to perform key management and mounting
functions.

Notable enhancements include:

• a new package, ecryptfs-utils-gui, has been added to this update. This
  package depends on the pygtk2 and pygtk2-libglade packages and provides the
  eCryptfs Mount Helper GUI program. To install the GUI, first install
  ecryptfs-utils and then issue the following command:

  yum install ecryptfs-utils-gui

(BZ#500997)

• the “ecryptfs-rewrite-file” utility is now more intelligent when dealing
  with non-existent files and with filtering special files such as the “.”
  directory. In addition, the progress output from “ecryptfs-rewrite-file”
  has been improved and is now more explicit about the success status of each
  target. (BZ#500813)

• descriptions of the “verbose” flag and the “verbosity=[x]” option, where
  [x] is either 0 or 1, were missing from a number of eCryptfs manual pages,
  and have been added. Refer to the eCryptfs man pages for important
  information regarding using the verbose and/or verbosity options.
  (BZ#470444)

These updated packages also fix the following bugs:

• mounting a directory using the eCryptfs mount helper with an RSA key that
  was too small did not allow the eCryptfs mount helper to encrypt the entire
  key. When this situation occurred, the mount helper did not display an
  error message alerting the user to the fact that the key size was too
  small, possibly leading to corrupted files. The eCryptfs mount helper now
  refuses RSA keys which are to small to encrypt the eCryptfs key.
  (BZ#499175)

• when standard input was redirected from /dev/null or was unavailable,
  attempting to mount a directory with the eCryptfs mount helper caused it to
  become unresponsive and eventually crash, or an “invalid value” error
  message, depending on if the “–verbosity=[value]” option was provided as
  an argument, and, if so, its value. With these updated packages, attempting
  to mount a directory using “mount.ecryptfs” under the same conditions
  results in either the mount helper attempting to use default values (if
  “verbosity=0” is supplied), or an “invalid value” error message (instead of
  the mount helper hanging) if standard input is redirected and
  “–verbosity=1” is supplied, or that option is omitted entirely.
  (BZ#499367)

• attempting to use the eCryptfs mount helper with an OpenSSL key when the
  keyring did not contain enough space for the key resulted in an unhelpful
  error message. The user is now alerted when this situation occurs.
  (BZ#501460)

• the eCryptfs mount helper no longer fails upon receiving an incorrect or
  empty answer to “yes/no” questions. (BZ#466210)

Users are advised to upgrade to these updated ecryptfs-utils packages,
which resolve these issues and add these enhancements.

Merged security bulletin from advisories:
https://lists.centos.org/pipermail/centos-announce/2009-September/078307.html
https://lists.centos.org/pipermail/centos-announce/2009-September/078308.html

Affected packages:
ecryptfs-utils
ecryptfs-utils-devel
ecryptfs-utils-gui

Upstream details at:
https://access.redhat.com/errata/RHSA-2009:1307