RE: Email webbugs

[Javier Palomares Lopez <Jpalomares () abasesores es>]

U have an option to avoid send a confirmation in: 
Tools => Options => Preferences tab => E-mail options => Tracking options 
This sequence in Outlook 2000 but in OE and in other versions is very
similar.

But this isn´t the real problem. A hacker with a webserver could watch if
your account is active, just adding a small pic and watching when did you
loaded it in his logs.

Also, He could watch your IP, your Browser and/or email client, ...

Finally, I suggest that for improve your neighbourhood security, use when
it´s possible, plain text clients and send only plain text mails.

Regards, Javier Palomares.

--------------------------------------------------------------

Tenemos la opción de rechazar las confirmaciones en:
Herramientas => Opciones => Pestaña de preferencias => Opciones de correo e.
=> Opciones de seguimiento. Esta secuencia es para Outlook 2000, pero para
otras versiones y para el OE es muy parecido.

Pero el problema de verdad no es ese. Un hacker con un webserver puede ver
si tu cuenta está activa, simplemente añadiendo una imagen pequeña y
viendolo después en los logs.

Además de confirmar que tu cuenta está activa puede ver la fecha, IP,
navegador, y/o cliente de correo, ...

Por ultimo para mejorar la seguridad en vuestro entorno, sugiero que en lo
posible, se usen clientes de texto plano y se manden mails solo en texto
plano.

Saludos. Javier Palomares.

-----Mensaje original-----
De: abuse [mailto:postmaster () getinfo org]
Enviado el: lunes 27 de agosto de 2001 14:13
Para: Focus-MS
CC: VULN-DEV@SECURITYFOCUS. COM; BUGTRAQ@SECURITYFOCUS. COM;
win2ksecadvice () LISTSERV NTSECURITY NET
Asunto: Email webbugs


One of the things that has always bothered me about Outlook Express and
Outlook is that they are susceptable to webbugs. Basically there are no
options to block confirmation of your reading an email so any spammer can
verify that your address is active as long as they can get you to just view
an email.

A lot of people have difficulty understanding exactly what this means so I
set up a demonstration page at http://www.nthelp.com/OEtest/oe.htm in an
attempt to raise awareness of this nonsense and get MS to do something about
it. I don't know if other email programs like Eudora and Netscape are
vulnerable to email webbugs so if anyone tests those please let me know the
results.

Anyway, I've made the test site available to the public now so if you want
to check your email reader, feel free.

Geo.