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.

SLPJS (npm package slpjs) before version 0.27.2, has a vulnerability where users could experience false-negative validation outcomes for MINT transaction operations. A poorly implemented SLP wallet could allow spending of the affected tokens which would result in the destruction of a user's minting baton. This is fixed in version 0.27.2.

A specially crafted Bitcoin script can cause a discrepancy between the specified SLP consensus rules and the validation result of the slpjs npm package. An attacker could create a specially crafted Bitcoin script in order to cause a hard-fork from the SLP consensus. Affected users can upgrade to any version >= 0.21.4.