Security Vulnerability in the Solaris 10 TCP Fusion Code May Lead to a System Panic, Resulting in a Denial of Service (DoS)

Sun(sm) Alert Notification
     * Sun Alert ID: 102667
     * Synopsis: Security Vulnerability in the Solaris 10 TCP Fusion Code
       May Lead to a System Panic, Resulting in a Denial of Service (DoS)
     * Category: Security
     * Product: Solaris 10 Operating System
     * BugIDs: 6348581
     * Avoidance: Patch, Workaround
     * State: Resolved
     * Date Released: 17-Oct-2006
     * Date Closed: 17-Oct-2006
     * Date Modified:

1. Impact

   Solaris 10 systems may panic in the tcp_fuse_rcv_drain() TCP/IP
   function when using TCP loopback connections, where both ends of the
   connection are on the same system. This may allow a local unprivileged
   user to cause a Denial of Service (DoS) condition on the affected
   host.

2. Contributing Factors

   This issue can occur in the following releases:

   SPARC Platform
     * Solaris 10 without patch 118833-23

   x86 Platform
     * Solaris 10 without patch 118855-19

   Note: Solaris 8 and Solaris 9 are not impacted by this issue.

3. Symptoms

   A system panic in tcp_fuse_rcv_drain() TCP/IP function is
   representative of this issue.

4. Relief/Workaround

   To work around the described issue until patches can be installed,
   disable TCP Fusion by adding the following line to the "/etc/system"
   file and rebooting the system:
    set ip:do_tcp_fusion = 0x0

   Undo the above change to the "/etc/system" file and reboot to
   re-enable TCP Fusion.

   Note: The workaround option above may affect performance.

5. Resolution

   This issue is addressed in the following releases:

   SPARC Platform
     * Solaris 10 with patch 118833-23 or later

   x86 Platform
     * Solaris 10 with patch 118855-19 or later

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