Summary

Name: Potential issues with Ethereal 0.9.3

Docid: enpa-sa-00004

Date: May 19, 2002

Versions affected: 0.9.3 and earlier

Severity: High

Details

Description:

Four potential security issues have been discovered in Ethereal 0.9.3:

• The SMB dissector could potentially dereference a NULL pointer in two cases.

• The X11 dissector could potentially overflow a buffer while parsing keysyms.

• The DNS dissector could go into an infinite loop while reading a malformed packet.

• The GIOP dissector could potentially allocate large amounts of memory.

No known exploits exist "in the wild" at the present time for any of these issues.

Versions prior to 0.9.3 are also subject to these bugs. In order to determine which version of Ethereal you have installed, do one of the following:

• Load Ethereal and go to the Help->About Ethereal... menu item.

• From the command line run

  ethereal -v

  or

  tethereal -v

  (the "v" is lowercase").

Either action will display the the application version along with the libraries that Ethereal and Tethereal are linked with. If version "0.9.3" or prior is displayed, the application is susceptible.

Impact:

It may be possible to make Ethereal crash or hang by injecting a purposefully malformed packet onto the wire, or by convincing someone to read a malformed packet trace file. It may be possible to make Ethereal run arbitrary code by exploiting the buffer and pointer problems.

Resolution:

Upgrade to 0.9.4.

If you are running a version prior to 0.9.4, you can disable the dissectors for each of these protocols by selecting Edit->Protocols... and deselecting them from the list.