RHSA-2011:0920 - Security Advisory

Topic

Updated krb5-appl packages that fix one security issue are now available
for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having
important 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 krb5-appl packages provide Kerberos-aware telnet, ftp, rcp, rsh, and
rlogin clients and servers. While these have been replaced by tools such as
OpenSSH in most environments, they remain in use in others.

It was found that gssftp, a Kerberos-aware FTP server, did not properly
drop privileges. A remote FTP user could use this flaw to gain unauthorized
read or write access to files that are owned by the root group.
(CVE-2011-1526)

Red Hat would like to thank the MIT Kerberos project for reporting this
issue. Upstream acknowledges Tim Zingelman as the original reporter.

All krb5-appl users should upgrade to these updated packages, which contain
a backported patch to correct this issue.

Solution

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

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

Affected Products

• Red Hat Enterprise Linux Server 6 x86_64
• Red Hat Enterprise Linux Server 6 i386
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 6.1 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support 6 i386
• Red Hat Enterprise Linux Workstation 6 x86_64
• Red Hat Enterprise Linux Workstation 6 i386
• Red Hat Enterprise Linux Desktop 6 x86_64
• Red Hat Enterprise Linux Desktop 6 i386
• Red Hat Enterprise Linux for IBM z Systems 6 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 6.1 s390x
• Red Hat Enterprise Linux for Power, big endian 6 ppc64
• Red Hat Enterprise Linux for Power, big endian - Extended Update Support 6.1 ppc64
• Red Hat Enterprise Linux for Scientific Computing 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 x86_64
• Red Hat Enterprise Linux Server from RHUI 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support (for IBM z Systems) 6 s390x
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Update Support from RHUI 6.1 i386
• Red Hat Virtual Storage Appliance (from RHUI) 6.1 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 x86_64
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension 6 i386
• Red Hat Enterprise Linux Server - Extended Life Cycle Support Extension (for IBM z Systems) 6 s390x

Fixes

• BZ - 711419 - CVE-2011-1526 krb5, krb5-appl: ftpd incorrect group privilege dropping (MITKRB5-SA-2011-005)

CVEs

• CVE-2011-1526

References

• https://access.redhat.com/security/updates/classification/#important
• http://web.mit.edu/kerberos/advisories/MITKRB5-SA-2011-005.txt