Critical · published December 9, 2025
🚨 An exploited preimage hash in NUT-14 is a recipe for disaster! Attackers can create cashu tokens that fill the mint's database with junk data, causing chaos in no time! 🔥 Picture a restaurant that accepts any dish order without checking if it's even on the menu — they end up with a kitchen overflowing with unidentifiable meals that nobody can eat! That's what happens with NUT-14 when the preimage size isn't validated! If this vulnerability is exploited, an attacker could bombard the mint's database, leading to potentially catastrophic storage issues and service downtime. This could cripple operations and require extensive cleanup, making it a seriously threatening situation for any system that uses this component.
Picture a restaurant that accepts any dish order without checking if it's even on the menu — they end up with a kitchen overflowing with unidentifiable meals that nobody can eat! That's what happens with NUT-14 when the preimage size isn't validated! This vulnerability allows cashu tokens to be created without validating the size of the preimage hash when spent. As a result, attackers can fill the mint's database and disk with arbitrary data, overwhelming the system.
If this vulnerability is exploited, an attacker could bombard the mint's database, leading to potentially catastrophic storage issues and service downtime. This could cripple operations and require extensive cleanup, making it a seriously threatening situation for any system that uses this component. Upgrade to nuts version 0.18.0 or higher immediately to patch this vulnerability. Implement strict validation on preimage sizes when tokens are spent to prevent exploitation. Regularly monitor your database for unusual data patterns to catch any abuse early! You've got this! Take action now, and you'll keep your systems running smoothly and securely! 🛡️
| Product | Versions | Fixed in |
|---|---|---|
| cashu/nutshell | < 0.18.0 | 0.18.0 |