RHSA-2007:0951 - Security Advisory

Topic

An updated nfs-utils-lib package to correct two security flaws is now
available for Red Hat Enterprise Linux 5.

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

Description

The nfs-utils-lib package contains support libraries that are needed by the
commands and daemons of the nfs-utils package.

The updated nfs-utils package fixes the following vulnerabilities:

Tenable Network Security discovered a stack buffer overflow flaw in the RPC
library used by nfs-utils-lib. A remote unauthenticated attacker who can
access an application linked against nfs-utils-lib could trigger this flaw
and cause the application to crash. On Red Hat Enterprise Linux 5 it is not
possible to exploit this flaw to run arbitrary code as the overflow is
blocked by FORTIFY_SOURCE. (CVE-2007-3999)

Tony Ernst from SGI has discovered a flaw in the way nfsidmap maps NFSv4
unknown uids. If an unknown user ID is encountered on an NFSv4 mounted
filesystem, the files will default to being owned by 'root' rather than
'nobody'. (CVE-2007-4135)

Users of nfs-utils-lib are advised to upgrade to this updated package,
which contains backported patches to resolve these issues.

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/FAQ_58_10188

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 - 250973 - CVE-2007-3999 krb5 RPC library buffer overflow
• BZ - 254040 - CVE-2007-4135 nfs-utils-lib NFSv4 user id mapping flaw

CVEs

• CVE-2007-3999
• CVE-2007-4135

References

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