CVE-2026-42193

CRITICAL EPSS 2.7%

Published May 8, 20261mo ago · Modified Jun 17, 20262w ago

9.1 CVSS 3.1

Critical

Published May 8, 2026 1mo ago

Last Modified Jun 17, 2026 2w ago

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.

CVSS Details

Base Score

9.1

Exploitability

3.9

Impact

5.2

Vector string

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Attack Vector Network

Attack Complexity Low

Privileges Required None

User Interaction None

Scope Unchanged

Confidentiality None

Integrity High

Availability High

Threat Intelligence

EPSS Exploit Probability

2.7% percentile

Exploit & Patch Status

No Known Exploit

No Patch Available

Weaknesses 1

CWE-347

References 2

github.com https://github.com/useplunk/plunk/releases/tag/v0.9.0
github.com https://github.com/useplunk/plunk/security/advisories/GHSA-9792-w86v-gx53

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.