checkout-storybook-default (npm) · Malicious Code
Affects checkout-storybook-defaultSource GCVE Database
Malicious package : remove checkout-storybook-default and rotate any secrets on hosts that installed it.
Data as of 5 Aug 2026, 16:04 UTC
Malicious package
Published to npm · OSV MAL-2026-12593
What to do
Remove checkout-storybook-default from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| npmcheckout-storybook-default | Affected
| Fixed in– |
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Description
The npm package 'checkout-storybook-default' version 35.5.1 contains malicious code that, upon requiring the package, loads a polyfill script which reconstructs command-and-control hostnames at runtime. It downloads an opaque binary payload over HTTPS using a spoofed user-agent and can fallback to a covert DNS-TXT channel. The payload is saved to a hidden cache path with a decoy filename, given executable permissions, and executed detached from the parent process. The malware includes sandbox evasion techniques and uses marker files to prevent repeated execution. This behavior is unrelated to the package's stated functionality.