Updated nss_ldap packages fix buffer overflow

Updated nss_ldap packages are now available for Red Hat Linux 6.2, 7, 7.1,
7.2, and 7.3. These updates fix a potential buffer overflow which can occur
when nss_ldap is set to configure itself using information stored in DNS,
a format string bug in logging functions used in pam_ldap, and to properly
handle truncated DNS responses.

nss_ldap is a set of C library extensions that allow X.500 and LDAP
directory servers to be used as a primary source of aliases, ethers,
groups, hosts, networks, protocols, users, RPCs, services, and shadow
passwords (instead of or in addition to using flat files or NIS).

When versions of nss_ldap prior to nss_ldap-198 are configured without a
value for the "host" setting, nss_ldap will attempt to configure itself by
using SRV records stored in DNS. When parsing the results of the DNS
query, nss_ldap does not check that the data returned by the server will
fit into an internal buffer, leaving it vulnerable to a buffer overflow.
The Common Vulnerabilities and Exposures project (cve.mitre.org) has
assigned the name CAN-2002-0825 to this issue.

When versions of nss_ldap prior to nss_ldap-199 are configured without a
value for the "host" setting, nss_ldap will attempt to configure itself by
using SRV records stored in DNS. When parsing the results of the DNS
query, nss_ldap does not check that the data returned has not been
truncated by the resolver libraries to avoid a buffer overflow, and may
attempt to parse more data than is actually available, leaving it
vulnerable to a read buffer overflow.

Versions of pam_ldap prior to version 144 include a format string bug in
the logging function. The packages included in this erratum update pam_ldap
to version 144, fixing this bug. The Common Vulnerabilities and Exposures
project (cve.mitre.org) has assigned the name CAN-2002-0374 to this issue.

All users of nss_ldap should update to these errata packages which are not
vulnerable to the above issues. The errata packages are based on
nss_ldap-189 with the addition of a backported security patch and pam_ldap
version 144.

Thanks to the nss_ldap and pam_ldap team at padl.com for providing
information about these issues.

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

To update all RPMs for your particular architecture, run:

rpm -Fvh [filenames]

where [filenames] is a list of the RPMs you wish to upgrade. Only those
RPMs which are currently installed will be updated. Those RPMs which are
not installed but included in the list will not be updated. Note that you
can also use wildcards (*.rpm) if your current directory *only* contains the
desired RPMs.

Please note that this update is also available via Red Hat Network. Many
people find this an easier way to apply updates. To use Red Hat Network,
launch the Red Hat Update Agent with the following command:

up2date

This will start an interactive process that will result in the appropriate
RPMs being upgraded on your system.

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-0374
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2002-0825
http://www.padl.com/Articles/PotentialBufferOverflowin.html
http://www.padl.com/OSS/pam_ldap.html
http://archives.neohapsis.com/archives/vulnwatch/2002-q2/0053.html
http://www.kb.cert.org/vuls/id/738331

automatic, configuration, dns, MAXPACKET, nss_ldap