constructor-blocks-mailings (npm) · Malicious Code
Affects constructor-blocks-mailingsSource GCVE Database
Malicious package : remove constructor-blocks-mailings 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-2026-12662
What to do
Remove constructor-blocks-mailings 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 |
|---|---|---|
| npmconstructor-blocks-mailings | Affected
| Fixed in– |
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Description
The npm package 'constructor-blocks-mailings' version 35.5.7 contains malicious code that, upon being required, downloads and executes an opaque binary from obfuscated Cloudflare Workers endpoints. This binary is fetched via a covert DNS-TXT base64 fallback channel, saved under disguised filenames in temporary directories, given executable permissions, and executed detached from the main process. The package uses string fragment assembly to evade static detection and does not verify the integrity of the downloaded binary. This behavior constitutes a hostile install-time dropper.