blockchainProhard

The Timekeeper's Paradox

CompFest 18 / COMPFEST 2026 blockchain CTF

Task: source-less DeFi challenge — drain a 50 ETH lending pool using only on-chain bytecode. Solution: heimdall decompilation exposed a proxy whose multicall reaches the self-gated setPendingAdmin; admin takeover plus an immutable-price evil oracle enabled uncollateralized borrows that drained the pool.

blockchain solidity defi proxy oracle_manipulation storage_collision decompilation evm

bytecode_decompilationselector_resolutionproxy_admin_takeovermulticall_self_call_bypassstorage_collision_avoidancespot_price_oracle_manipulationuncollateralized_borrow_drain

$ ls tags/ techniques/

blockchain solidity defi proxy oracle_manipulation storage_collision decompilation evm

bytecode_decompilationselector_resolutionproxy_admin_takeovermulticall_self_call_bypassstorage_collision_avoidancespot_price_oracle_manipulationuncollateralized_borrow_drain

Analysis

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$ python3 exploit.py --target 192.168.1.1 --port 8080
[*] Connecting to target...
[+] Shell obtained!

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