NUT-14 allows cashu tokens to be created with a preimage hash. However, nutshell (cashubtc/nuts) before 0.18.0 do not validate the size of preimage when the token is spent. The preimage is stored b...

Not analysed yet

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Severity and exploitation

• CISA KEV Not listed.
• EPSS 0.0045, the 39th percentile, on 9 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of OSV, published 8 Dec 2025. New records show when each source confirmed them.

Sources

• OSV: PYSEC-2025-89
• delvingbitcoin.org/t/public-disclosure-denial-of-service-using-htlc-in-cashu/2090
• preimage007.github.io/

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.