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More Than Meets the Eye
ττ²τΊτΈτ«τΊ·τ§»ττΈ
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More Than Meets the Eye
Zero-width space (ZWSP)
Problem
My friend just sent me this file, but it looks pretty empty. Are you able to see anything?
Solution
Opening up the file in a hex editor, we can see that the "empty space" is essentially repetitions of either
E280 8BE2 808C
or
E280 8CE2 808C
.
We can convert this to binary where
E280 8BE2 808C
-> 0 and
E280 8CE2 808C
-> 1.
1
from
Crypto
.
Util
.
number
import
*
2
β
3
with
open
(
'zwsp.txt'
,
'rb'
)
as
f
:
4
data
=
f
.
read
()
5
β
6
i
=
0
7
curr
=
[]
8
β
9
bin_string
=
''
10
β
11
for
char
in
data
:
12
if
char
not
in
b'Pretty empty over here'
:
13
i
+=
1
14
curr
.
append
(
char
)
15
if
i
%
3
==
0
:
16
i
=
0
17
print
(
curr
)
18
β
19
if
curr
[
-
1
]
==
139
:
20
bin_string
+=
'0'
21
else
:
22
bin_string
+=
'1'
23
β
24
curr
=
[]
25
β
26
print
(
bin_string
)
27
print
(
int
(
bin_string
,
2
))
28
print
(
long_to_bytes
(
int
(
bin_string
,
2
)))
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ττ²τΊτΈτ«τΊ·τ§»ττΈ
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1mo ago
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Contents
Problem
Solution