eacq-payform-core

Details

**Severity:** Critical

**Affected versions:** `= 20.3.6`

## Source: amazon-inspector (ac90938ceb191a40f640c12f11258ef8a518d24480072eeaa0791a155a49c724)
On require() of the package, index.js loads _vendor.js which selects a platform-specific endpoint, fetches an opaque binary over HTTPS from Cloudflare Workers subdomains whose hostnames are reconstructed at runtime by joining split string fragments (e.g. "oob-worker.cf102-ba"+"f.w"+"orkers.dev"), with a DNS TXT chunked-base64 fallback channel (c.<domain> for chunk count, then N.<domain> TXT queries reassembled via Buffer.from(parts.join(""), "base64")). The fetched bytes are written under a disguised name (dot-file or dotnet_diag masquerade) in /var/tmp or %TEMP%, chmod 0o755 on POSIX, then detached-spawned via /bin/sh -c or cmd.exe. Package advertises itself only as a 'platform core' with no legitimate need for platform-detected binary execution. Host strings are deliberately fragmented to evade static analysis; a rate-limit marker is written to /tmp/.analytics_state or %TEMP%\analytics_state.

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Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/78792aee23e5c759f309a3d2e9397caf2439773e/osv/malicious/npm/eacq-payform-core/MAL-2026-11538.json))

**References:**
- https://github.com/ossf/malicious-packages/blob/78792aee23e5c759f309a3d2e9397caf2439773e/osv/malicious/npm/eacq-payform-core/MAL-2026-11538.json
- https://www.npmjs.com/package/eacq-payform-core/v/20.3.6
- https://github.com/ossf/malicious-packages/blob/71b5ccd62809b0f6e173eff59b5900130cf7fc02/osv/malicious/npm/eacq-payform-core/MAL-2026-11538.json
- https://github.com/advisories/GHSA-jf7f-ppjr-9c4w

Compromised versions (1)

• = 20.3.6

Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.