# THORChain Upgrade Fixes Rujira Exploit

> THORChain v3.21 upgrade targets Rujira smart contract flaw after exploit.
- Title: THORChain Upgrade Fixes Rujira Exploit · TokenPost | Shortify
- Summary: THORChain v3.21 upgrade targets Rujira smart contract flaw after exploit. THORChain plans to restart Rujira trading after fixing a smart contract exploit…
- Keywords: thorchain, rujira, smart contract, exploit, v3.21 upgrade, app layer, credit account, loan to value, node operators, crypto, finance, Upgrade
- Source: TokenPost — https://tokenpost.com/news/technology/36104
- Published: 2026-10-20T23:29:59+00:00
- Read time: 1 min
- Topics: thorchain, rujira, smart contract, exploit, v3.21 upgrade, app layer, credit account, loan to value, node operators, crypto, finance
## THORChain Upgrade Targets Rujira
THORChain plans to patch a Rujira smart contract flaw in its v3.21 upgrade to restart trading after an exploit halted Rujira’s app layer.
## Exploit Details
The exploit reported Sept. 26 involved FIN’s position-transfer function, allowing an attacker to move a custom concentrated liquidity position they did not own.
## Restart Plan
Rujira will ask node operators to lift the pause on its services after the upgrade succeeds, with a conditional safeguard for borrowers exceeding 100% loan-to-value ratios.
## Key takeaway

THORChain plans to restart Rujira trading after fixing a smart contract exploit that halted its app layer.