Another cgiemail bug

From: sec (
Date: 06/14/02

Date: Fri, 14 Jun 2002 17:20:55 +0300 (EEST)
From: sec <>
To: <>, <>, <>, <>, <>

Yet another cgiemail and others bug.
Not much to report, so we'll keep it concise.

It's on open relaying bug. This vulnerability affects cgiemail and a lot
of other web/mail applications, we are concentrating on cgiemail because
it is considered safe. The same kind of exploit can be performed on many
similar apps using the blessed "sendmail -t" to send the mail and avoid
the bad attacker getting a shell.

The problem is very few developers filter the new line code "%0a". When
posting data to the web/mail application, the remote user can take one of
the predefined variables and add "%0a" followed by additional fields
decoded by sendmail. For example CC: or Bcc: and so on. The result is that
the mail is going to a lot of other addresses.



Simple, clear enough.

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