CVE-2013-220 - out-of-bounds reads in autofs and ssh responder

[Timo Aaltonen]

================= A security bug in SSSD 1.8 and 1.9 ===============
=
= Subject: out-of-bounds reads in autofs and ssh responder
=
= CVE ID#: CVE-2013-0220
=
= Summary: Multiple out-of-bounds buffer read flaws were found in
= the way the autofs and ssh responders of the SSSD
= performed the parsing of input packet values. An attacker
= could crash the autofs and ssh responders with the use
= of a carefully crafted packet written to the responder
= sockets.
=
=
= Impact: low
=
= Acknowledgements: The bug was found by Florian Weimer of the Red Hat
= Product Security team
=
= Affects default
= configuration: yes (as generated by ipa-client-install)
=
= Introduced with: 1.8.0
=
===============================================================

==== DESCRIPTION ====

SSSD versions 1.8.0 through 1.9.3 are vulnerable to a security bug.

The functions that parse the incoming data packet from client applications
in both the ssh and autofs responders do not check the string lengths against
the packet length correctly. An attacker could exploit the bug and crash
the autofs or the ssh responder with the use of a specially crafted packet
sent to the responder sockets, causing a temporary denial of service.

If you are not using the autofs or SSH integration, you can disable the
vulnerable responders by removing "ssh" or "autofs" respectively from the
list of services configured in the [sssd] section of the SSSD config file.

The default configuration of a client of FreeIPA - as generated by
ipa-client-install - is affected because the ssh responder is enabled
by default.

The fix will be delivered as part of the upcoming 1.9.4 release. There won't
be a separate 1.9 security release as the 1.9.4 version will be released later
this week. The flaw will be fixed in a separate release for the 1.8 and 1.5 LTM
releases as well.

The bug is being tracked in the following Red Hat Bugzilla report:
https://bugzilla.redhat.com/show_bug.cgi?id=884601

==== PATCH AVAILABILITY ====

The patch is available at:
http://git.fedorahosted.org/cgit/sssd.git/patch/?id=2bd514cfde1938b1e245af11c9b548d58d49b325

[Timo Aaltonen (tjaalton)]

fixed for raring in 1.9.3-0ubuntu2

[Adam Conrad (adconrad)]

Hello Timo, or anyone else affected,

Accepted sssd into precise-proposed. The package will build now and be available at http://launchpad.net/ubuntu/+source/sssd/1.8.6-0ubuntu0.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Adam Conrad (adconrad)]

Hello Timo, or anyone else affected,

Accepted sssd into quantal-proposed. The package will build now and be available at http://launchpad.net/ubuntu/+source/sssd/1.9.1-0ubuntu1.2 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Timo Aaltonen (tjaalton)]

This bug was fixed in the package sssd - 1.8.6-0ubuntu0.2

---------------
sssd (1.8.6-0ubuntu0.2) precise-proposed; urgency=low

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