[clamav-users] Errir parsing PNG files and 451_mail_server_temporarily_rejected_message

[G.W. Haywood]

Hi there,

On Tue, 3 Nov 2020, Micah Snyder (micasnyd) via clamav-users wrote:

> Just took a look - it seems that image001.gif is missing the final
> byte, a value "0x3B" should be at the end of every GIF file.
> ...
> I wonder if this is a common occurrence.  ...

It seems to be common enough to need to be able to cope with it.

I just ran 'locate' on my laptop to find every .gif file on the box,
piped the output through 'tail -c1' and 'hexdump -f something' to get
the final byte of each file in hex, through a 'perl -ap' one-liner to
count the distinct final bytes, and finally through 'sort'.

Results from 5970 GIF files:

01 1
3e 1
ad 1
82 7
0a 8
d9 32
00 45
3b 5875

I've almost no idea where all these files came from.  Many will have
been parts of packages, many will be just interesting images that I
grabbed from articles I've read over the years.  It's possibile that
at least some of them are broken bits from failed browser processes
etc.  I spent no time looking for clues.  Many of the files are very
old.  The oldest file is 26 years old - as it happens, to the day!

Please let me know if I can do any more with this.

-- 

73,
Ged.