Plunk is an open-source email platform built on top of AWS SES. Prior to version 0.9.0, the /webhooks/sns endpoint accepts Amazon SNS notification payloads from unauthenticated requests without verifying the SNS signature, certificate, or topic ARN, meaning anyone can forge a valid-looking webhook request. This allows an unauthenticated attacker to spoof SNS events to trigger workflow automations, unsubscribe contacts, manipulate email delivery metrics, and potentially exhaust billing credits. This issue has been patched in version 0.9.0.

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History

Fri, 08 May 2026 23:15:00 +0000

Type Values Removed Values Added
First Time appeared Useplunk
Useplunk plunk
Vendors & Products Useplunk
Useplunk plunk

Fri, 08 May 2026 21:45:00 +0000

Type Values Removed Values Added
Description Plunk is an open-source email platform built on top of AWS SES. Prior to version 0.9.0, the /webhooks/sns endpoint accepts Amazon SNS notification payloads from unauthenticated requests without verifying the SNS signature, certificate, or topic ARN, meaning anyone can forge a valid-looking webhook request. This allows an unauthenticated attacker to spoof SNS events to trigger workflow automations, unsubscribe contacts, manipulate email delivery metrics, and potentially exhaust billing credits. This issue has been patched in version 0.9.0.
Title Plunk: SNS webhook forgery
Weaknesses CWE-347
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-08T21:12:26.450Z

Reserved: 2026-04-25T01:53:21.584Z

Link: CVE-2026-42193

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-05-08T22:16:31.273

Modified: 2026-05-08T22:16:31.273

Link: CVE-2026-42193

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-08T23:00:15Z

Weaknesses