Plunk has SSRF via unvalidated AWS SNS SubscriptionConfirmation in POST /webhooks/sns

published 2026-03-11 7 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-11336

cvss: 9.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 24%
public exploits: 0; none known

Plunk is an open-source email platform built on top of AWS SES. Prior to 0.7.0, a Server-Side Request Forgery (SSRF) vulnerability existed in the SNS webhook handler. An unauthenticated attacker could send a crafted request that caused the server to make an arbitrary outbound HTTP GET request to any host accessible from the server. This vulnerability is fixed in 0.7.0.

Patch / fix

fixed in 1 links 1

useplunk plunk 0.7.0

github.com/useplunk/plunk@b8f1ad9 commit

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 7 mo ago (2026-03-12)

Exploit prediction

0.31% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
NVD	3.1	8.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

Affected products

useplunk plunk

Classification

Weakness

CWE-918 Server-Side Request Forgery

References

Sources

CVE List CVE-2026-32096
NVD CVE-2026-32096

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary