1060711 - 1MiB (big) text file Attachment Almost Freezes the Thunderbird

Status: RESOLVED DUPLICATE of bug 564051

(Thunderbird :: Message Reader UI, defect)

Description

[martin.vahi]

User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:31.0) Gecko/20100101 Firefox/31.0 (Beta/Release)
Build ID: 20140715214327

Steps to reproduce:


Reproduction:

1) Create a text file that is at least 1MiB big
   and contains only one, single, line of text. 

2) Send a letter that contains that text file as an attachment.

2) Try to open that letter at outbox.

Eventually the letter is displayed and the content of
the 1MiB single-liner text file is also displayed,
but it takes more than 1 minute on a ~3GHz machine
to generate the view.

Proposal:

If the attachment is of "text file" MIME type and
its size is greater than 5k-characters, then
the content of the text file should not be "previewed".



Suspicion:

May be the same flaw exists with other file types.
How about a 200MiB JPEG?


Security:

I don't agree with the policy that security holes
should be hidden till they are fixed, but this
might be a nice way to create semi-DoS attacks
to end-users. Just send a plain Christmas greeting
that has a huge, single-liner, text file as an
attachment and hope that a whole office full of
officials tries to open that letter and experiment
with Thunderbird till they figure out, what's causing
the freeze. Quite a nuisance.

Comment 1

[martin.vahi]

May be it has something to do with 
the fact that the rendering of 

http://tools.ietf.org/rfc/index

is terribly slow in Debian distribution 
of the Iceweasel?

I was thinking of filing that as a separate flaw,
but may be they are both just related to the 
rendering code path.

Comment 2

[martin.vahi]

May be there is a relation between the current bug and 
the bug 245960.

Comment 3

[michalzuber86]

Have the same issue with big XML (over 6MB) in preview
http://i.imgur.com/V0nJDcH.png

Comment 4

[michalzuber86]

(In reply to michalzuber86 from comment #3)
> Have the same issue with big XML (over 6MB) in preview
> http://i.imgur.com/V0nJDcH.png

I'm using Thunderbird 45 on OSX.
Checked in OSX Mail and they don't provide preview, so it's fast :)

Comment 5

[michalzuber86]

Found solution at http://superuser.com/questions/110058/prevent-thunderbird-from-trying-to-display-large-plain-text-attachments/110068#110068
TB has a switch for it.