In SLPJS (npm package slpjs) before version 0.27.4, there is a vulnerability to false-positive validation outcomes for the NFT1 Child Genesis transaction type. A poorly implemented SLP wallet or opportunistic attacker could create a seemingly valid NFT1 child token without burning any of the NFT1 Group token type as is required by the NFT1 specification. This is fixed in version 0.27.4.

Affected: npm: slpjs

### Impact In the npm package named "slpjs", versions prior to 0.27.4 are vulnerable to false-positive validation outcomes for the NFT1 Child Genesis transaction type. A poorly implemented SLP wallet or opportunistic attacker could create a seemingly valid NFT1 child token without burning any of the NFT1 Group token type as is required by the NFT1 specification.

### Patches npm package "slpjs" has been patched and is published and tagged as version 0.27.4.

### Workarounds Upgrade to slpjs 0.27.4.

### References * Package location: https://www.npmjs.com/package/slpjs * SLP NFT1 spec: https://slp.dev/specs/slp-nft-1/#nft1-protocol-requirements * Git commit hash fixing this issue: https://github.com/simpleledger/slpjs/commit/290c20e8bff13ac81459d43e54cac232b5e3456c * Unit tests have been added to assist validator implementations in avoiding this bug: https://github.com/simpleledger/slp-unit-test-data/commit/8c942eacfae12686dcf1f3366321445a4fba73e7

### For more information If you have any questions or comments about this advisory please open an issue in the [slp-validate](https://github.com/simpleledger/slpjs/issues) repository.