CVE-2012-1182: "root" credential remote code execution

[Rey Tucker]

CVE-2012-1182 was recently made public for a remote, unauthenticated, root code execution flaw in most samba versions 3.0+:

https://www.samba.org/samba/security/CVE-2012-1182

I believe Ubuntu's packages to be vulnerable. As the CVE is already public and patches are in the wild, I am flagging this as a security vulnerability but will un-privatize it shortly.

[Jan (jan-redhat-bugs)]

Multiple heap-based buffer overflow flaws were found in the way the code generated by Perl-based DCE/RPC IDL (PIDL) compiler of the Samba suite performed array memory allocation. Memory for an array having an is_size() attribute has been allocated based on the array length, which was provided by the Network Data Representation (NDR) marshalling code (converting parameters provided to the RPC call by the client to the NDR). On the other hand the loop retrieving array elements for a particular array used variable indicated by the size_is() attribute. A remote attacker could provide a specially-crafted remote procedure call (RPC) parameters, which once processed by the marshalling code of the Samba server would lead to Samba daemon (smbd) crash, or, potentially arbitrary code execution with the privileges of the user running the server.

[Vincent (vincent-redhat-bugs)]

This has been corrected in upstream 3.6.4, 3.5.14, and 3.4.16.

External References:

http://www.samba.org/samba/history/samba-3.6.4.html

[errata-xmlrpc (errata-xmlrpc-redhat-bugs)]

This issue has been addressed in following products:

  Red Hat Enterprise Linux 5.6 EUS - Server Only
  Red Hat Enterprise Linux 5

Via RHSA-2012:0466 https://rhn.redhat.com/errata/RHSA-2012-0466.html

[errata-xmlrpc (errata-xmlrpc-redhat-bugs)]

This issue has been addressed in following products:

  Red Hat Enterprise Linux 5.3 Long Life
  Red Hat Enterprise Linux 5.6 EUS - Server Only
  Red Hat Enterprise Linux 5
  Red Hat Enterprise Linux 6.0 EUS - Server Only
  Red Hat Enterprise Linux 6.1 EUS - Server Only
  Red Hat Enterprise Linux 6

Via RHSA-2012:0465 https://rhn.redhat.com/errata/RHSA-2012-0465.html

[Vincent (vincent-redhat-bugs)]

This is an automatically created tracking bug! It was created to ensure
that one or more security vulnerabilities are fixed in affected Fedora
versions.

For comments that are specific to the vulnerability please use bugs filed
against "Security Response" product referenced in the "Blocks" field.

For more information see:
http://fedoraproject.org/wiki/Security/TrackingBugs

When creating a Bodhi update request, please include this bug ID and the
bug IDs of this bug's parent bugs filed against the "Security Response"
product (the top-level CVE bugs). Please mention the CVE IDs being fixed
in the RPM changelog when available.

Bodhi update submission link:
https://admin.fedoraproject.org/updates/new/?type_=security&bugs=804093

Please note: this issue affects multiple supported versions of Fedora.
Only one tracking bug has been filed; please ensure that it is only closed
when all affected versions are fixed.

[bug automatically created by: add-tracking-bugs]

[Vincent (vincent-redhat-bugs)]

Created samba tracking bugs for this issue

Affects: fedora-all [bug 811392]

[Tyler Hicks (tyhicks)]

Thanks, Ryan! We are aware of the issue and we are currently working on an update.

[Jan (jan-redhat-bugs)]

*** Bug 811543 has been marked as a duplicate of this bug. ***

[Fedora (fedora-redhat-bugs)]

samba-3.6.4-82.fc17.1 has been submitted as an update for Fedora 17.
https://admin.fedoraproject.org/updates/samba-3.6.4-82.fc17.1

[Fedora (fedora-redhat-bugs)]

samba-3.6.4-82.fc16 has been submitted as an update for Fedora 16.
https://admin.fedoraproject.org/updates/samba-3.6.4-82.fc16

[Fedora (fedora-redhat-bugs)]

samba-3.5.14-73.fc15.1 has been submitted as an update for Fedora 15.
https://admin.fedoraproject.org/updates/samba-3.5.14-73.fc15.1

[Gwyn (gwyn-redhat-bugs)]

Rawhide has been updated, updates have been created for f17, f16 and f15.

[Tyler Hicks (tyhicks)]

Here is my proposed debdiff for Precise. I'll need a sponsor for this to make it into the release.

I've built a package locally with this debdiff. I sanity checked it using the 'umt compare-log', 'umt compare-bin', and 'umt check' tools. I tested it with the reproducers from ZDI, as well as test-samba.py in the qa-regression-testing project. The reproducers were mitigated with the update and tset-samba.py passed successfully.

[Jelmer Vernooij (jelmer)]

Hi Tyler,

+1 on the diff, that looks good.

Note that an alternative to shipping the second patch is to update the generated files from the package itself, so the diff isn't massive; this would require adding "make -C source3 samba3-idl" as part of the build step and adding libparse-yapp-perl to the build dependencies.

I should be able to sponsor, though it's well past my EOD, so it might be better if somebody else could.

[Tyler Hicks (tyhicks)]

Thanks Jelmer! You've probably already noticed, but jdstrand has sponsored it.

I was wondering if we could generate the PIDL generated code at build time, but I decided against it for sake of making cherry-picking from upstream stable branches easy in the future. Upstream has reran the PIDL compiler and committed that as a change, so any new security backports that they do will be based upon the regenerated code. It seems like it would be in our best interest to follow what upstream did. Any thoughts?

[Tyler Hicks (tyhicks)]

Ok, now I see that the 3.6 upstream branch places the samba3-idl target underneath 'make all', so I assume that they are now relying on the code generation to happen at build time. Can you confirm this, Jelmer?

If that's the case, then we probably do want to follow that convention in our 3.6.x and later packages (currently only found in Precise). The reason is that if we don't do it at build time, but upstream does, one of their patches that we cherry-pick could theoritically need to be ran through PIDL to make proper changes. I _think_ that's the case, but I'm still not quite knowldgeable on the PIDL compiler to know for sure.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "samba_3.6.3-2ubuntu2.debdiff" of this bug report has been identified as being a patch in the form of a debdiff. The ubuntu-sponsors team has been subscribed to the bug report so that they can review and hopefully sponsor the debdiff. In the event that this is in fact not a patch you can resolve this situation by removing the tag 'patch' from the bug report and editing the attachment so that it is not flagged as a patch. Additionally, if you are member of the ubuntu-sponsors team please also unsubscribe the team from this bug report.

[This is an automated message performed by a Launchpad user owned by Brian Murray. Please contact him regarding any issues with the action taken in this bug report.]

[Launchpad Janitor (janitor)]

This bug was fixed in the package samba - 2:3.5.11~dfsg-1ubuntu2.2

---------------
samba (2:3.5.11~dfsg-1ubuntu2.2) oneiric-security; urgency=low

  * SECURITY UPDATE: Unauthenticated remote code execution via
    RPC calls (LP: #978458)
    - debian/patches/CVE-2012-1182-1.patch: Fix PIDL compiler to generate code
      that uses the same value for array allocation and array length checks.
      Based on upstream patch.
    - debian/patches/CVE-2012-1182-2.patch: Regenerate PIDL generated files with
      the patched PIDL compiler
    - CVE-2012-1182
 -- Tyler Hicks <email address hidden> Thu, 12 Apr 2012 05:28:44 -0500

[Launchpad Janitor (janitor)]

This bug was fixed in the package samba - 2:3.5.8~dfsg-1ubuntu2.4

---------------
samba (2:3.5.8~dfsg-1ubuntu2.4) natty-security; urgency=low

  * SECURITY UPDATE: Unauthenticated remote code execution via
    RPC calls (LP: #978458)
    - debian/patches/CVE-2012-1182-1.patch: Fix PIDL compiler to generate code
      that uses the same value for array allocation and array length checks.
      Based on upstream patch.
    - debian/patches/CVE-2012-1182-2.patch: Regenerate PIDL generated files with
      the patched PIDL compiler
    - CVE-2012-1182
 -- Tyler Hicks <email address hidden> Thu, 12 Apr 2012 05:28:44 -0500

[Launchpad Janitor (janitor)]

This bug was fixed in the package samba - 2:3.4.7~dfsg-1ubuntu3.9

---------------
samba (2:3.4.7~dfsg-1ubuntu3.9) lucid-security; urgency=low

  * SECURITY UPDATE: Unauthenticated remote code execution via
    RPC calls (LP: #978458)
    - debian/patches/CVE-2012-1182-1.patch: Fix PIDL compiler to generate code
      that uses the same value for array allocation and array length checks.
      Based on upstream patch.
    - debian/patches/CVE-2012-1182-2.patch: Regenerate PIDL generated files with
      the patched PIDL compiler
    - CVE-2012-1182
 -- Tyler Hicks <email address hidden> Thu, 12 Apr 2012 05:28:44 -0500

[Launchpad Janitor (janitor)]

This bug was fixed in the package samba - 3.0.28a-1ubuntu4.18

---------------
samba (3.0.28a-1ubuntu4.18) hardy-security; urgency=low

  [ Steve Beattie ]
  * SECURITY UPDATE: unauthenticated remote code execution via
    RPC calls (LP: #978458)
    - debian/patches/security-CVE-2012-1182.patch: make variable length
      check be consistent with memory allocation size computation.
    - CVE-2012-1182
 -- Tyler Hicks <email address hidden> Thu, 12 Apr 2012 05:28:44 -0500

[Launchpad Janitor (janitor)]

This bug was fixed in the package samba - 2:3.6.3-2ubuntu2

---------------
samba (2:3.6.3-2ubuntu2) precise-proposed; urgency=low

  * SECURITY UPDATE: Unauthenticated remote code execution via
    RPC calls (LP: #978458)
    - debian/patches/CVE-2012-1182-1.patch: Fix PIDL compiler to generate code
      that uses the same value for array allocation and array length checks.
      Based on upstream patch.
    - debian/patches/CVE-2012-1182-2.patch: Regenerate PIDL generated files
      with the patched PIDL compiler
    - CVE-2012-1182
 -- Tyler Hicks <email address hidden> Thu, 12 Apr 2012 05:28:44 -0500

[Fedora (fedora-redhat-bugs)]

Package samba-3.6.4-82.fc17.1:
* should fix your issue,
* was pushed to the Fedora 17 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing samba-3.6.4-82.fc17.1'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2012-5793/samba-3.6.4-82.fc17.1
then log in and leave karma (feedback).

[Huzaifa (huzaifa-redhat-bugs)]

Created samba4 tracking bugs for this issue

Affects: fedora-all [bug 812257]

[errata-xmlrpc (errata-xmlrpc-redhat-bugs)]

This issue has been addressed in following products:

  Red Hat Enterprise Linux 4 Extended Lifecycle Support

Via RHSA-2012:0478 https://rhn.redhat.com/errata/RHSA-2012-0478.html

[Fedora (fedora-redhat-bugs)]

samba-3.6.4-82.fc16 has been pushed to the Fedora 16 stable repository. If problems still persist, please make note of it in this bug report.

[Fedora (fedora-redhat-bugs)]

samba-3.6.4-82.fc17.1 has been pushed to the Fedora 17 stable repository. If problems still persist, please make note of it in this bug report.

[Fedora (fedora-redhat-bugs)]

samba-3.5.14-73.fc15.1 has been pushed to the Fedora 15 stable repository. If problems still persist, please make note of it in this bug report.

[Tomas (tomas-redhat-bugs)]

Statement:

This issue did not affect the versions of samba packages as shipped with Red Hat Enterprise Linux 3. The samba packages are also excluded from the Red Hat Enterprise Linux 3 Extended Life Cycle Support coverage:
http://www.redhat.com/rhel/server/extended_lifecycle_support/exclusions/

[Fedora (fedora-redhat-bugs)]

samba4-4.0.0-38.alpha16.fc16 has been pushed to the Fedora 16 stable repository. If problems still persist, please make note of it in this bug report.

[Huzaifa (huzaifa-redhat-bugs)]

Statement:

This issue affects the version of samba4, openchange and evolution-mapi packages as shipped with Red Hat Enterprise Linux 6. A future security update may address this flaw.

[Huzaifa (huzaifa-redhat-bugs)]

This flaw exists in the samba PIDL code, and therefore affects the PIDL compiler shipped within the samba4 package (samba4-pidl). However we do not ship any daemon with the samba4 package, hence the impact of this flaw on samba4 is very limited.

The samba4-pidl compiler is also used to compile code in the openchange and evolution-mapi packages. These contain client side code for exchanging data with MAPI servers. In order to successfully exploit vulnerabilities in these packages, arising out of the above flaw in samba4-pidl, one will need to MITM the connection between these clients and the MAPI servers. Hence the impact on these packages is limited as well.

[errata-xmlrpc (errata-xmlrpc-redhat-bugs)]

This issue has been addressed in following products:

  Red Hat Enterprise Linux 6

Via RHSA-2013:0506 https://rhn.redhat.com/errata/RHSA-2013-0506.html

[errata-xmlrpc (errata-xmlrpc-redhat-bugs)]

This issue has been addressed in following products:

  Red Hat Enterprise Linux 6

Via RHSA-2013:0515 https://rhn.redhat.com/errata/RHSA-2013-0515.html