RHSA-2015:2417 - Security Advisory

Topic

Updated autofs packages that fix one security issue, several bugs, and add
one enhancement are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having Moderate security
impact. A Common Vulnerability Scoring System (CVSS) base score, which
gives a detailed severity rating, is available from the CVE link in the
References section.

Description

The autofs utility controls the operation of the automount daemon. The
daemon automatically mounts file systems when in use and unmounts them when
they are not busy.

It was found that program-based automounter maps that used interpreted
languages such as Python used standard environment variables to locate
and load modules of those languages. A local attacker could potentially use
this flaw to escalate their privileges on the system. (CVE-2014-8169)

Note: This issue has been fixed by adding the "AUTOFS_" prefix to the
affected environment variables so that they are not used to subvert the
system. A configuration option ("force_standard_program_map_env") to
override this prefix and to use the environment variables without the
prefix has been added. In addition, warnings have been added to the manual
page and to the installed configuration file. Now, by default the standard
variables of the program map are provided only with the prefix added to
its name.

Red Hat would like to thank the Georgia Institute of Technology for
reporting this issue.

Notably, this update fixes the following bugs:

• When the "ls *" command was run in the root of an indirect mount, autofs

attempted to literally mount the wildcard character (*) causing it to be
added to the negative cache. If done before a valid mount, autofs then
failed on further mount attempts inside the mount point, valid or not. This
has been fixed, and wildcard map entries now function in the described
situation. (BZ#1166457)

• When autofs encountered a syntax error consisting of a duplicate entry in

a multimap entry, it reported an error and did not mount the map entry.
With this update, autofs has been amended to report the problem in the log
to alert the system administrator and use the last seen instance of the
duplicate entry rather than fail. (BZ#1205600)

• In the ldap and sss lookup modules, the map reading functions did not

distinguish between the "no entry found" and "service not available"
errors. Consequently, when the "service not available" response was
returned from a master map read, autofs did not update the mounts.
An "entry not found" return does not prevent the map update, so the ldap
and sss lookup modules were updated to distinguish between these two
returns and now work as expected. (BZ#1233065)

In addition, this update adds the following enhancement:

• The description of the configuration parameter map_hash_table_size was

missing from the autofs.conf(5) man page and its description in the
configuration file comments was insufficient. A description of the
parameter has been added to autofs.conf(5), and the configuration file
comments have been updated. (BZ#1238573)

All autofs users are advised to upgrade to these updated packages, which
contain backported patches to correct these issues and add this
enhancement.

Solution

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

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux Server 7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.5 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 7.3 x86_64
• Red Hat Enterprise Linux Server - AUS 7.7 x86_64
• Red Hat Enterprise Linux Server - AUS 7.6 x86_64
• Red Hat Enterprise Linux Server - AUS 7.4 x86_64
• Red Hat Enterprise Linux Server - AUS 7.3 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 7 x86_64
• Red Hat Enterprise Linux Workstation 7 x86_64
• Red Hat Enterprise Linux Desktop 7 x86_64
• Red Hat Enterprise Linux for IBM z Systems 7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.7 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.5 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.4 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 7.3 s390x
• Red Hat Enterprise Linux for Power, big endian 7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.7 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.5 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.4 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 7.3 ppc64
• Red Hat Enterprise Linux for Scientific Computing 7 x86_64
• Red Hat Enterprise Linux Server from RHUI 7 x86_64
• Red Hat Enterprise Linux for Power, little endian 7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.7 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.6 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.5 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.4 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.3 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 7.2 ppc64le
• Red Hat Enterprise Linux Server - TUS 7.7 x86_64
• Red Hat Enterprise Linux Server - TUS 7.6 x86_64
• Red Hat Enterprise Linux Server - TUS 7.3 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 7 s390x
• Red Hat Enterprise Linux EUS Compute Node 7.7 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.6 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.5 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.4 x86_64
• Red Hat Enterprise Linux EUS Compute Node 7.3 x86_64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.7 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.6 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.4 ppc64le
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 7.3 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.7 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.6 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.4 x86_64
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 7.3 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, big endian 7 ppc64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support for IBM Power, little endian 7 ppc64le

Fixes

• BZ - 1161474 - automount segment fault in parse_sun.so for negative parser tests
• BZ - 1166457 - Autofs unable to mount indirect after attempt to mount wildcard
• BZ - 1192565 - CVE-2014-8169 autofs: priv escalation via interpreter load path for program based automount maps
• BZ - 1201582 - autofs: MAPFMT_DEFAULT is not macro in lookup_program.c
• BZ - 1218045 - Similar but unrelated NFS exports block proper mounting of "parent" mount point
• BZ - 1233067 - autofs is performing excessive direct mount map re-reads
• BZ - 1233069 - Direct map does not expire if map is initially empty
• BZ - 1263508 - Heavy program map usage can lead to a hang

CVEs

• CVE-2014-8169

References

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