CVE-2023-32517Network attack vector

Unauthenticated user redirection via unvalidated destination

Published Dec 29, 2023 · Updated Apr 28, 2026

Open redirect in PluginOps MailChimp Subscribe Forms 4.0.9.3 and earlier allows remote attackers to redirect users via crafted input. The redirect handling accepts a user-supplied destination without validating that its URL belongs to the site; public advisories do not identify the responsible parameter or handler. Exploitation is unauthenticated but requires a user to follow a crafted link, enabling redirection from a trusted site to an attacker-chosen site for phishing.

CVSS severity4.7
Medium
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Open redirect in PluginOps MailChimp Subscribe Forms 4.0.9.3 and earlier allows remote attackers to redirect users via crafted input. The redirect handling accepts a user-supplied destination without validating that its URL belongs to the site; public advisories do not identify the responsible parameter or handler. Exploitation is unauthenticated but requires a user to follow a crafted link, enabling redirection from a trusted site to an attacker-chosen site for phishing.

The record

CVE
CVE-2023-32517
Published
Dec 29, 2023
Updated
Apr 28, 2026
Vendor
PluginOps
Product
MailChimp Subscribe Form, Optin Builder, PopUp Builder, Form Builder
Classifications
CWE-601, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 29, 2023CVE publishedPublication date reported by the CVE source.
  2. Apr 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a <=4.0.9.3 changes=[{"at":"4.0.9.4","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

PluginOps · MailChimp Subscribe Form, Optin Builder, PopUp Builder, Form Builderversion=n/a <=4.0.9.3 changes=[{"at":"4.0.9.4","status":"unaffected"}]

Published CVSS scores

4.7PatchstackCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-601URL Redirection to Untrusted Site ('Open Redirect')
T1204.001Malicious Link

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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