Embedded Malicious Code Affecting is-arrayish package, versions =0.3.3
Threat Intelligence
Snyk has reported that there have been attempts or successful attacks targeting this vulnerability.
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- published16 Sept 2025
- disclosed15 Sept 2025
- creditUnknown
Introduced: 15 Sep 2025
New Malicious CVE-2025-59331 (opens in a new tab)How to fix?
Avoid using all malicious instances of the is-arrayish package.
Overview
Affected versions of this package are vulnerable to Embedded Malicious Code. This package version contains malicious code that monitors network traffic when run in a browser and targets crypto transactions. The injected malicious code activates a hook whenever a Web3 wallet is present. Once triggered, it intercepts and alters any transaction with ETH value, redirecting it to another address likely controlled by the attacker. The malicious code also listens for swap and transfer transactions to manipulate as well.