6a0877384d
- Remove undeployed challenges: Phantom_Byte, Cr4cK_w1f1, Lain_Br34kC0r3 V1, Lain_VS_Knights, Lets_All_Love_UART, AETHER_NET, Last_Train_451, Web3/ - Sync 24 solve/ files from main CTF-Espilon repo - Update all READMEs with real CTFd final scores at freeze - Add git-header.png banner - Rewrite README: scoreboard top 10, edition stats (1410 users, 264 boards, 1344 solves), correct freeze date March 26 2026
46 lines
601 B
Markdown
46 lines
601 B
Markdown
# Serial Experimental 00 -- Solution
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## Overview
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The challenge provides a split UART interface:
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- TX (read): `1111`
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- RX (write): `2222`
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Goal: recover token and run `unlock <token>`.
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## Steps
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1. Open both channels:
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```bash
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nc <host> 1111
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nc <host> 2222
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```
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2. Query diagnostics from RX:
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```text
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diag.uart
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diag.eeprom
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diag.order
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```
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3. Recover fragments:
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- `frag_a_hex=4c41494e` -> `LAIN`
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- `frag_b_xor_hex=4056415a525f` with `xor_key=0x13` -> `SERIAL`
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- `frag_c_hex=3030` -> `00`
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4. Build token:
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`LAIN-SERIAL-00`
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5. Unlock:
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```text
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unlock LAIN-SERIAL-00
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```
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6. Flag is returned on TX.
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