contract-contract-builder (npm) · Malicious Code
Affects contract-contract-builderSource GCVE Database
Malicious package : remove contract-contract-builder and rotate any secrets on hosts that installed it.
Data as of 5 Aug 2026, 16:20 UTC
Malicious package
Published to npm · OSV MAL-2026-12665
What to do
Remove contract-contract-builder 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 |
|---|---|---|
| npmcontract-contract-builder | Affected
| Fixed in– |
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Description
The npm package 'contract-contract-builder' version 35.5.2 contains malicious code that downloads and executes a platform-specific binary from dynamically assembled Cloudflare Workers hosts. This binary is saved to temporary directories with disguised filenames, given executable permissions, and launched detached from the main process. If HTTPS delivery fails, a DNS TXT record fallback channel reconstructs a base64 payload from multiple DNS TXT records. The package falsely advertises itself as a UI toolkit, but the fetched binary is unrelated, unverified, and executed automatically upon import.