GLSA-200803-31 : MIT Kerberos 5: Multiple vulnerabilities

This script is Copyright (C) 2008-2014 Tenable Network Security, Inc.


Synopsis :

The remote Gentoo host is missing one or more security-related
patches.

Description :

The remote host is affected by the vulnerability described in GLSA-200803-31
(MIT Kerberos 5: Multiple vulnerabilities)

Two vulnerabilities were found in the Kerberos 4 support in
KDC: A global variable is not set for some incoming message types,
leading to a NULL pointer dereference or a double free()
(CVE-2008-0062) and unused portions of a buffer are not properly
cleared when generating an error message, which results in stack
content being contained in a reply (CVE-2008-0063).
Jeff
Altman (Secure Endpoints) discovered a buffer overflow in the RPC
library server code, used in the kadmin server, caused when too many
file descriptors are opened (CVE-2008-0947).
Venustech AD-LAB
discovered multiple vulnerabilities in the GSSAPI library: usage of a
freed variable in the gss_indicate_mechs() function (CVE-2007-5901) and
a double free() vulnerability in the gss_krb5int_make_seal_token_v3()
function (CVE-2007-5971).

Impact :

The first two vulnerabilities can be exploited by a remote
unauthenticated attacker to execute arbitrary code on the host running
krb5kdc, compromise the Kerberos key database or cause a Denial of
Service. These bugs can only be triggered when Kerberos 4 support is
enabled.
The RPC related vulnerability can be exploited by a remote
unauthenticated attacker to crash kadmind, and theoretically execute
arbitrary code with root privileges or cause database corruption. This
bug can only be triggered in configurations that allow large numbers of
open file descriptors in a process.
The GSSAPI vulnerabilities could be exploited by a remote attacker to
cause Denial of Service conditions or possibly execute arbitrary code.

Workaround :

Kerberos 4 support can be disabled via disabling the 'krb4' USE flag
and recompiling the ebuild, or setting 'v4_mode=none' in the
[kdcdefaults] section of /etc/krb5/kdc.conf. This will only work around
the KDC related vulnerabilities.

See also :

http://www.gentoo.org/security/en/glsa/glsa-200803-31.xml

Solution :

All MIT Kerberos 5 users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose '>=app-crypt/mit-krb5-1.6.3-r1'

Risk factor :

Critical / CVSS Base Score : 10.0
(CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C)

Family: Gentoo Local Security Checks

Nessus Plugin ID: 31671 (gentoo_GLSA-200803-31.nasl)

Bugtraq ID:

CVE ID: CVE-2007-5894
CVE-2007-5971
CVE-2008-0062
CVE-2008-0063
CVE-2008-0947