Write-ups for TCTT2023/Network/02

Flag pattern

CTT23{xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}

Challenge Files

Solution

In this PCAP file there are very few packets, we just lookin into packet no.2 .

We can see the PK in the content which is the header of the zip file.

We copy the zip content of the packet in hex.

50 4b 03 04 14 00 00 00 08 00 aa 9d 1a 57 a1 8b
85 3f ad 01 00 00 bc 01 00 00 08 00 00 00 66 6c
61 67 2e 7a 69 70 75 90 5b 28 bb 71 1c c6 7f ef
fe ef fe 93 cc 4a b3 89 8d 99 f3 61 24 2e 94 b4
30 b5 8c da d6 44 0e cd 24 33 96 b6 c9 61 73 21
9b 86 94 37 29 f2 e6 7c 96 6c 8e 45 21 4b 0e 25
21 33 76 b1 a4 68 48 89 92 39 7b 1b 25 17 9e 6f
df e7 a9 a7 cf d5 c3 e7 fd 83 c9 00 00 17 d0 df
e3 9d c5 81 6f 27 82 21 00 58 d8 bb 60 6d b1 5c
22 8d d2 c8 14 95 08 9b 8b 53 92 b7 4e 33 f5 79
fe a8 92 93 9a cf f0 a4 16 11 e9 49 22 e9 7c fe
3a 51 d0 c6 09 1a 86 85 fe f3 f1 30 45 26 60 b9
a7 a5 10 0f f6 0b ea 18 83 5a d5 f4 9a b6 7c 9b
29 6a d0 d3 c2 5f 1b 2f 99 0e bb 3d ac 49 77 ba
55 8b 3c 9e dd d5 88 5b a7 0c 32 18 c4 9c b4 a2
63 d1 b9 73 31 09 68 b7 5a 2b 9c 14 9b 1f bc 3b
8f 2d 8f 8d 4a 6a 80 cd 32 52 3d 75 4f 47 19 a3
71 8b 72 84 f6 62 76 74 18 8c 9b 29 be 04 6b 6c
c5 33 93 c7 45 fa 2e 0a 9f 8d 26 c5 f8 58 86 db
13 fd 10 b5 b1 df ea ab a2 a9 7b e9 72 7c fb 72
e2 08 cd 31 2b 24 d9 43 74 fa 25 75 e9 d0 1c 4b
4d 55 84 86 35 ef d0 05 5c 0f 9b 09 71 5f 98 29
ab 28 39 bf ba b1 a8 ce c8 19 ab 77 11 ef d3 e2
23 a9 06 31 dc f7 6a 32 7b ac 85 b5 6f 2b 1f 52
92 79 6d 26 fb 28 54 a4 11 43 f8 b6 64 56 97 a9
05 d6 05 2f 4a 28 4d 14 23 49 a7 1a d8 19 cc 91
10 36 22 af 11 dc 2e c4 e7 41 38 36 f8 6b cd 40
f0 25 86 d3 7f b6 75 fd 6e 20 e0 05 a2 36 08 7e
3e 27 56 8c ff 2d 3e 0f ff df c9 60 97 83 65 ba
93 f8 04 50 4b 01 02 3f 00 14 00 00 00 08 00 aa
9d 1a 57 a1 8b 85 3f ad 01 00 00 bc 01 00 00 08
00 24 00 00 00 00 00 00 00 20 00 00 00 00 00 00
00 66 6c 61 67 2e 7a 69 70 0a 00 20 00 00 00 00
00 01 00 18 00 59 40 c2 2b 1b d8 d9 01 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 50 4b 05
06 00 00 00 00 01 00 01 00 5a 00 00 00 d3 01 00
00 00 00 0d 0a