claims-format-masked-phone-number (npm) · Malicious Code
Affects claims-format-masked-phone-numberSource GCVE Database
Malicious package : remove claims-format-masked-phone-number and rotate any secrets on hosts that installed it.
Data as of 5 Aug 2026, 16:12 UTC
Malicious package
Published to npm · OSV MAL-2026-12617
What to do
Remove claims-format-masked-phone-number 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 |
|---|---|---|
| npmclaims-format-masked-phone-number | Affected
| Fixed in– |
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Description
The npm package 'claims-format-masked-phone-number' version 35.9.8 contains malicious code that loads a polyfill script which fetches and executes opaque native binaries from hardcoded Cloudflare Workers subdomains. These binaries are saved to temporary directories and executed without any signature verification. A fallback mechanism uses DNS TXT record queries to retrieve and run additional executable code. The package's behavior and included files do not align with its stated purpose of phone-number masking, indicating malicious intent.