Plunk · Plunk · CVE-2026-42193
**Name of the Vulnerable Software and Affected Versions**
Plunk versions prior to 0.9.0
**Description**
The '/webhooks/sns' endpoint accepts Amazon SNS notification payloads from unauthenticated requests without verifying the SNS signature, certificate, or topic ARN. This allows an unauthenticated attacker to forge webhook requests and spoof SNS events to trigger workflow automations, unsubscribe contacts, manipulate email delivery metrics, and potentially exhaust billing credits.
**Recommendations**
Update to version 0.9.0.
As a temporary workaround, restrict access to the '/webhooks/sns' endpoint to minimize the risk of exploitation.