Summary

• This advisory describes a vulnerability that affects Cisco products and applications that are installed on the Solaris operating system, and is based on the vulnerability of an common service within the Solaris operating system, not due to a defect of the Cisco product or application. A vulnerability in the "cachefs" program was discovered that enables an attacker to execute arbitrary code under Solaris OS. This vulnerability was publicly announced in the CERT Advisory CA-2002-11. All Cisco products and applications that are installed on Solaris OS are considered vulnerable to the underlying operating system vulnerability, unless the workaround was applied. This vulnerability is described in details in Sun(sm) Alert Notification at http://sunsolve.sun.com/search/document.do?assetkey=1-26-44309-1 .

  No other Cisco product is vulnerable.

  Sun is working on a patch. Until the patch is released all affected customers are advised to apply the workaround described in the workaround section.

  This advisory is available at https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20020724-solaris-cachefs.

Affected Products

• This section provides details on affected products.

  Vulnerable Products

  All products that are based on the following Solaris releases are affected:

  • Solaris 2.5.1
    
  • Solaris 2.6
    
  • Solaris 7
    
  • Solaris 8
    

  The following products are affected:

  • Media Gateway Controller (MGC) and Related Products
    
    • Products running on Solaris 2.5.1 are vulnerable unless CSCOh013.pkg release 1.0(9) or later has been installed. The product that is based on this version of Solaris is Signaling Controller 2200 (SC2200).
      
    • Products running on Solaris 2.6 are vulnerable unless CSCOh013.pkg release 1.0(9) or later has been installed. Products running on Solaris 8 are vulnerable unless CSCOh013.pkg release 2.0(2) or later has been installed. The products that are based on these versions of Solaris are:
      
      • SC2200
        
      • Cisco Virtual Switch Controller (VSC3000)
        
      • Cisco PGW2200 Public Switched Telephone Network (PSTN) Gateway
        
      • Cisco Billing and Management Server (BAMS)
        
      • Cisco Voice Services Provisioning Tool (VSPT)
        
  • Cisco Element Management Framework (CEMF) and Related Products
    All releases of CEMF are vulnerable. The related products are:
    
    • Cisco 12000 Manager
      
    • Cisco DSL Manager
      
    • Element Manager Software for the Cisco 7200 and 7400 Series Routers
      
    • Element Manager Software for the Catalyst 6500 Series & Cisco 7600 Series Routers
      
    • Universal Gateway Manager
      
    • Cisco Cable Manager
      
    • Cisco Media Gateway Manager
      
    • Cisco MGC (Media Gateway Controller) Node Manager
      
  • Cisco IP Manager
    All releases.
    
  • Cisco Secure ACS for Unix
    All releases.
    

  Products Confirmed Not Vulnerable

  The following products are not affected:

  • BTS10200
    
  • Cisco IDS
    

  No other Cisco products are currently known to be affected by these vulnerabilities.

Details

• This vulnerability is described in the following advisories/notifications:

  • Sun Alert Notification at http://sunsolve.sun.com/search/document.do?assetkey=1-26-44309-1 .
    
  • CERT Advisory CA-2002-11 at http://www.cert.org/advisories/CA-2002-11.html .
    
  • This issue is also being referenced as CAN-2002-0033 (see http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2002-0033 ).
    

  A remotely exploitable heap overflow exists in the cachefsd program. It is installed by default on the Sun Solaris OS. Cachefsd caches requests for operations on remote file systems mounted via the use of NFS protocol. An attacker can send a crafted RPC request to the cachefsd program to exploit the vulnerability.

  According to Sun Microsystems, failed attempts to exploit this vulnerability may leave a core dump file in the root directory. Note that the core file may be created by some other process and that its presence is not a certain sign of a compromise. Additionally, if the file /etc/cachefstab exists, it may contain entries other than a known cache directories (e.g., /cachefs/cache0).

Workarounds

• The workaround is applicable to all Cisco products mentioned in the advisory. For MGC and related products, if you have applied the script from CSCO013.pkg you are protected and you do not have to apply this workaround.

  Comment out cachefsd in /etc/inetd.conf as shown below:

  • For Solaris 2.6, 7 and 8:
    

    #100235/1 tli rpc/tcp wait root /usr/lib/fs/cachefs/cachefsd  cachefsd

  • Solaris 2.5.1:
    

    #100235/1 stream rpc/tcp wait root /usr/lib/fs/cachefs/cachefsd  cachefsd

  Once the line is commented out either:

  • Reboot, or
    
  • Send a HUP signal to inetd(1M) and kill existing cachefsd processes, for example, on Solaris 2.5.1 and 2.6 do the following:
    

    $ kill -HUP <PID of inetd>
           $ kill <PIDs of any cachefsd processes> 

    Solaris 7 and 8 do the following:
    

    $ pkill -HUP inetd
           $ pkill cachefsd     

Fixed Software

• Sun Microsystem is working on a patch. Their latest status on this vulnerability is available at http://sunsolve.sun.com/search/document.do?assetkey=1-26-44309-1 .

Exploitation and Public Announcements

• According to CERT/CC the exploit program for this vulnerability is publicly available and there are credible reports that this vulnerability is actively being exploited.

URL

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20020724-solaris-cachefs

Revision History

• Revision 1.1	2002-July-25	Update to Details section
  Revision 1.0	2002-July-24	Initial public release

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