Re: Re: EMC Avamar: World writable cache files

[security_alert@xxxxxxx]

ESA-2013-003: EMC Avamar Client Elevation of Privilege Vulnerability

EMC Identifier: ESA-2013-003

CVE Identifier: CVE-2012-2291

Severity Rating: CVSS v2 Base Score: 6.8 (AV:L/AC:L/Au:S/C:C/I:C/A:C)
Affected products:  

?       EMC Avamar HP-UX Client 4.x, 5.x and 6.x
?       EMC Avamar Mac OS Client 4.x, 5.x and 6.x
?       EMC Avamar Plugin for Oracle 4.x, 5.x and 6.x

Note: Other Linux and Unix Avamar client systems could also be affected as a 
result of a support or locally-performed procedure that incorrectly sets the 
permission of the Avamar var directory (/usr/local/avamar/var or 
/opt/AVMRclnt/var).

Summary:  

Due to a vulnerability, described in detail below, the Avamar client leaves 
certain directories and files as world writable.  The presence of world 
writable directories and files may inadvertently result in elevation of 
privileges by a user who has access to the local file system. 

Details:  

The Avamar affected client process runs as root and after each backup it leaves 
the cache files as world readable and writable. While the cache files 
themselves do not contain sensitive information, when the parent directory is 
world-writable, the cache files could be used by an attacker to elevate the 
privileges when a system-level backup is performed.  The non-root user can 
create symbolic links to obtain unauthorized access to files on the affected 
system.

Note: This vulnerability information is currently public. EMC is not aware of 
any instance in which the vulnerability has been exploited maliciously.

Resolution:  

The following EMC Avamar product contains a resolution to this issue:

?       EMC Avamar Client Hotfix # 50184 (client version 6.1.101-89)

The Avamar client software must be upgraded by applying client hotfix #50184 
(client version 6.1.101-89). This hotfix first requires the Avamar Server to be 
upgraded to 6.1.0 or newer.
If your Avamar Server is already at 6.1.0 or newer, then you can upgrade your 
client version to 6.1.101-89.  See 
http://solutions.emc.com/emcsolutionview.asp?id=esg135935 for detailed 
instructions.

If you do not wish to upgrade your client software at this time, Tthe following 
workaround steps must be performed to mitigate the risk. until the full fix is 
available from EMC.

For HP-UX clients:
The permissions of the /opt/AVMRclnt/var directory should be set to 0755. 
Log into the HP-UX client as the ?root? user and type the following command:
chmod 0755 /opt/AVMRclnt/var

For Mac OS clients:
The permissions of the /var/avamar directory should be set to 0755. 
Log into the Mac client as the ?root? user and type the following command:
chmod 0755 /var/avamar

For Oracle clients:
The following procedure only applies to clients where the directory permissions 
of the Avamar var directory (/usr/local/avamar/var or /opt/AVMRclnt/var) have 
been manually changed after installation of the Avamar plugin for Oracle:
The permissions of the /usr/local/avamar/var should be set to 0775 with the 
group ownership set to the oracle group. Log into the Oracle client as the 
?root? user and type either of the following pairs of commands:

On Linux and Unix Oracle clients other than Solaris and HP-UX:

chmod 0775 /usr/local/avamar/var
chgrp oracle /usr/local/avamar/var

On Solaris and HP-UX Oracle clients:

chmod 0775 /opt/AVMRclnt/var
chgrp oracle /opt/AVMRclnt/var

Other Avamar clients:

 Verify that the permissions of the Avamar var directory (/usr/local/avamar/var 
or /opt/AVMRclnt/var) on Linux and Unix clients are not modified as a result of 
a support or locally-performed procedure. The permissions should be set to 0755.


If you have any questions or concerns about running the above commands please 
contact EMC Technical Support at http://www.emc.com/contact

[The following is standard text included in all security advisories.  Please do 
not change or delete.]

Read and use the information in this EMC Security Advisory to assist in 
avoiding any situation that might arise from the problems described herein. If 
you have any questions regarding this product alert, contact EMC Software 
Technical Support at 1-877-534-2867.

For an explanation of Severity Ratings, refer to EMC Knowledgebase solution 
emc218831. EMC recommends all customers take into account both the base score 
and any relevant temporal and environmental scores which may impact the 
potential severity associated with particular security vulnerability.

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attention of users of the affected EMC products, important security 
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