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Re: [Pulp-list] Pulp 2.8.3 Beta 1 released - Security & Bug fixes



On 04/25/2016 04:39 AM, Sean Myers wrote:
> The following Security issues were addressed in this release:
> 
> CVE-2016-3111 (Low Impact):
> pulp.spec generates its RSA keys for message signing insecurely
> https://pulp.plan.io/issues/1837
> 
> CVE-2016-3112 (Moderate Impact):
> Pulp consumer private keys are world-readable
> https://pulp.plan.io/issues/1834
> 
> CVE-2016-3107 (Moderate Impact):
> Node certificate containing private key stored in world-readable file
> https://pulp.plan.io/issues/1833
> 
> CVE-2016-3108 (Moderate Impact):
> Insecure temporary file used when generating certificate for Pulp Nodes
> https://pulp.plan.io/issues/1830
> 
> CVE-2016-3106 (Low Impact):
> Insecure creation of temporary directory when generating new CA key
> https://pulp.plan.io/issues/1827
> 
> Details on addressing these vulnerabilities will be released in a
> followup email later today, and included in subsequent release
> announcements for 2.8.3 (apologies for not being able to include
> them in this post).

CVE-2013-7450 (https://bugzilla.redhat.com/show_bug.cgi?id=1003326)
-------------

Additionally, CVE-2013-7450 was announced during this release cycle, even 
though it was fixed in Pulp 2.3.0. Users who have upgraded from Pulp < 2.3.0 
may still be vulnerable, action may be required (see below).

Upgrade instructions
====================

Some of the CVEs require user interaction to remedy. Begin by upgrading to  
Pulp 2.8.3:

$ sudo systemctl stop httpd pulp_workers pulp_resource_manager pulp_celerybeat goferd
$ sudo yum upgrade
$ sudo systemctl start httpd pulp_workers pulp_resource_manager pulp_celerybeat goferd

CVE-2016-3112 (Part I)
----------------------

The client certificate for consumers 
(/etc/pki/pulp/consumer/consumer-cert.pem) was installed world-readable. This 
issue has been fixed for new certificates issued to consumers, but upgrading 
to 2.8.3 does not modify the permissions of old certificates. It is  
recommended that users regenerate the certificates by unregistering and 
re-registering all consumers. However, the consumers cannot be re-registered 
until CVE-2013-7450, CVE-2016-3095, CVE-2016-3106, and CVE-2016-3111 have 
been addressed below. Thus, start by unregistering each of your consumers (we 
will return to this CVE later to re-register them):

$ sudo pulp-consumer unregister

CVE-2013-7450, CVE-2016-3095, and CVE-2016-3106
-----------------------------------------------

There are two reasons that you may wish to regenerate Pulp's internal 
certificate authority key and certificate. First, if your Pulp installation 
started off as a version lower than 2.3.0 and you are still using the default 
CA certificate and key that was distributed with those versions of Pulp, then 
you are still vulnerable to CVE-2013-7450 and it is crucial that you generate 
a new unique CA. 

Additionally, CVE-2016-3095 and CVE-2016-3106 made it possible for local 
attackers to read the CA key during generation (which happens during the 
initial installation of Pulp or any time an admin ran 
pulp-gen-ca-certificate). If you are concerned that a local user may have 
read that CA key during the brief window that it was visible it is  
recommended that you regenerate the key and cert.

To regenerate the certificate, you should remove the old one and then you may 
use the provided utility:

# First remove the old files so that the new files get the correct SELinux 
context.

$ sudo rm /etc/pki/pulp/ca.*
$ sudo pulp-gen-ca-certificate

If you choose not to perform the CA regeneration, you may wish to apply the 
correct SELinux type to your existing CA files as versions of Pulp < 2.8.3 
generated this file with an incorrect SELinux type. You don't need to do this 
if you removed the old file and regenerated it with pulp-gen-ca-certificate. 
You can run restorecon recursively on the /etc/pki/pulp folder to fix the 
SELinux label on your existing CA certificate:

# You only need to do this if you didn't regenerate the CA above.
$ sudo restorecon -R /etc/pki/pulp

CVE-2016-3107 and CVE-2016-3108
-------------------------------

For Nodes users, the /etc/pki/pulp/nodes/node.crt file was installed 
world-readable. Users are recommended to remove this file and regenerate it 
by running pulp-gen-nodes-certificate:

# It is important to remove the file so that the new file has the correct 
permissions.
$ sudo rm /etc/pki/pulp/nodes/node.crt
$ sudo pulp-gen-nodes-certificate

CVE-2016-3111
-------------

Both the RSA key pair for the Pulp server and RSA key pair for each Pulp 
consumer was generated during installation in an insecure directory. This 
vulnerability allowed a local attacker to read the private key portion of the 
key pair. These keys are used for message authentication between the Pulp 
server and the Pulp consumers. If you are concerned that a local attacker was 
able to read these keys, you can regenerate them. We do not ship a script to 
perform this, but the process is straight-forward. For the Pulp server, do 
the following as root:

$ cd /etc/pki/pulp/
$ rm rsa.key rsa_pub.key
$ umask 077
$ openssl genrsa -out rsa.key <bits>  # <bits> should be at least 2048
$ openssl rsa -in rsa.key -pubout > rsa_pub.key
$ chgrp apache rsa.key rsa_pub.key
$ chmod 640 rsa.key  # Apache must be able to read the private key
$ chmod 644 rsa_pub.key  # The public key is world-readable as it is served via Apache

The Pulp consumer key is similar:

$ cd /etc/pki/pulp/consumer/
$ rm rsa.key rsa_pub.key
$ umask 077
$ openssl genrsa -out rsa.key <bits>  # <bits> should be at least 2048
$ openssl rsa -in rsa.key -pubout > rsa_pub.key

CVE-2016-3112 (Part II)
-----------------------

Now that we have regenerated the server's CA certificate, we can finish 
re-registering each consumer to Pulp:

$ sudo pulp-consumer -u <admin-username> register --consumer-id=<consumer-id>

Restart
-------

Pulp services are now ready to be restarted again to pick up the new 
certificates. For systemd users:

$ sudo systemctl restart httpd pulp_workers pulp_resource_manager pulp_celerybeat goferd

Troubleshooting
---------------

Regenerating the CA certificate will invalidate all client certificates that 
were issued by the old CA. All users will need to login to Pulp again to 
obtain a new client certificate. If you forget a step, you may see one of the 
following error messages:

    "pulp.server.managers.auth.authentication:ERROR: Auth certificate with CN 
[admin:admin:57155b83e779896cb3d634a4] is signed by a foreign CA" (or 
similar) in the server log can indicate that httpd has not been restarted 
since the CA was replaced.
    "The specified user does not have permission to execute the given 
command" from pulp-admin can mean that the user has not logged in since the 
new CA was present, or that httpd has not been restarted since the 
certificate was replaced. More generally, this error message can also mean 
that the user is not authorized to perform the given action.
    "An error occurred attempting to contact the server. More information may 
be found using the -v flag." may be output by pulp-admin if you have 
restarted httpd but have not logged in again to get a new CA certificate. If 
you provide that -v flag and see "ConnectionException: (None, 'tlsv1 alert 
decrypt error', None)", this is likely the issue.



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