Several subscribers have received email messages, apparently from the tango lists, that contain the klez computer virus. This virus seems to be extremely virulent; I've been receiving several copies of it per day for a couple of weeks or so.
All of the copies of the klez virus that I've seen that looked like they came from the tango lists actually had forged return addresses. Forging the return email addresses is a trick often used by the klez virus. Forged return addresses can usually be recognized by examination of the internet headers that come with the mail message, but this requires an uncommon degree of knowledge of some fairly technical subjects. I have changed the ListServer's options so that it will reject posts that contain MIME attachments. This should reduce the chances of the ListServer distributing a virus (including the klez virus), but it is going to inconvenience some people. Subscribers who send posts to the list in MIME format may have those posts rejected directly by the ListServer instead of by the moderators. The ListServer's built in error messages do not explain the reason for rejection as well as the moderators' messages. There is little that the ListServer or the moderators can do about messages with forged return addresses, though, since they are not actually sent by the list. I have also changed the ListServer options for the tango-l list. Messages from tango-l should now have a "[TANGO-L] " prefix in the subject line. Any email with a tango-l return address that does not have that subject prefix should be considered suspicious. Likewise, all email from tango-a should have one of the geographic prefixes in the subject line. List digests should have the name of the list and the date in the subject line. Risks to internet users have become more frequent and more sophisticated each year. Detailed discussions of these risks is off topic for a tango list, and the information is readily available elsewhere. Briefly, though: opening email attachments is always dangerous, even if they appear to come from a trusted source. Viewing email in HTML and/or MIME is also generally dangerous; this is part of the reason why the tango lists require plain text format. For more information, check out www.cert.org and/or the various vendors of antivirus software. Jim Tango-a/l co-administrator
