RHSA-2009:1307 - Security Advisory

Topic

Updated ecryptfs-utils packages that fix a security issue, various bugs,
and add enhancements are now available for Red Hat Enterprise Linux 5.

This update has been rated as having low security impact by the Red Hat
Security Response Team.

Description

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.

Solution

Before applying this update, make sure that all previously-released
errata relevant to your system have been applied.

This update is available via Red Hat Network. Details on how to use
the Red Hat Network to apply this update are available at
http://kbase.redhat.com/faq/docs/DOC-11259

Affected Products

• Red Hat Enterprise Linux Server 5 x86_64
• Red Hat Enterprise Linux Server 5 ia64
• Red Hat Enterprise Linux Server 5 i386
• Red Hat Enterprise Linux Workstation 5 x86_64
• Red Hat Enterprise Linux Workstation 5 i386
• Red Hat Enterprise Linux Desktop 5 x86_64
• Red Hat Enterprise Linux Desktop 5 i386
• Red Hat Enterprise Linux for IBM z Systems 5 s390x
• Red Hat Enterprise Linux for Power, big endian 5 ppc
• Red Hat Enterprise Linux Server from RHUI 5 x86_64
• Red Hat Enterprise Linux Server from RHUI 5 i386

Fixes

• BZ - 460496 - ecryptfs complains about a missing module, fails and then loads it
• BZ - 472524 - CVE-2008-5188 ecryptfs-utils: potential provided password disclosure in the process table
• BZ - 475969 - difference between the name of the binary and the name in its usage message
• BZ - 482834 - RHEL5: update ecryptfs-utils to latest
• BZ - 499128 - `man ecryptfs' is wrong on what to write to openssl_passwd_file=XXX
• BZ - 499367 - mount.ecrytfs hangs when used with wrong/missing stdin
• BZ - 500352 - mount helper asks different set questions when the mount options are OK and when are not
• BZ - 500361 - [ecryptfs-add-passphrase] adding key, which is in keyring already, results in error msg
• BZ - 500566 - When kernel does not support filename encryption `ecryptfs-add-passphrase --fnek' should exit with exit code != 0
• BZ - 500623 - Access-Your-Private-Data.desktop file should have an icon associated
• BZ - 500804 - Typo in ecryptfs-rewrite-file(1)
• BZ - 500810 - ecryptfs-insert-wrapped-passphrase-into-keyring fails to add passphrase to keyring if the passphrase is in the keyring already
• BZ - 500813 - ecryptfs-rewrite-file should be more wise when dealing with non-existing/bogus files
• BZ - 500817 - ecryptfs-dot-private is not expected to be executed, remove the "x" permission
• BZ - 500820 - ecryptfs-setup-swap: vol_id: command not found
• BZ - 500824 - Possible missing runtime dependencies for `ecryptfs-setup-swap'
• BZ - 500829 - `ecryptfs-setup-swap' tries to restart service ``cryptdisks'' which is not present in RHEL/Fedora
• BZ - 500850 - [RFE] ecryptfs-manager should ask for password confirmation when creating openssl key
• BZ - 500997 - ecryptfs-utils-gui must require pygtk2-libglade
• BZ - 501275 - Select key bytes: item "default" is bogus
• BZ - 501460 - Error msg from ecryptfs-utils does not reflect reality when adding key to "full" keyring

CVEs

• CVE-2008-5188

References

• http://www.redhat.com/security/updates/classification/#low