CVE-2021-25033: Noptin < 1.6.5 - Open Redirect

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2022-02-14 · updated 2026-06-17
Weakness: CWE-601

Description

The WordPress Newsletter Plugin WordPress plugin before 1.6.5 does not validate the to parameter before redirecting the user to its given value, leading to an open redirect issue

Affected products

Noptin Newsletter Simple Newsletter Plugin – Noptin: before 1.6.5 — fixed in 1.6.5

How to fix

Upgrade to a fixed version: Noptin Newsletter Simple Newsletter Plugin – Noptin 1.6.5. Check the vendor advisory for mitigations.

References

https://plugins.trac.wordpress.org/changeset/2639592
https://wpscan.com/vulnerability/c2d2384c-41b9-4aaf-b918-c1cfda58af5c
https://plugins.trac.wordpress.org/changeset/2639592
https://wpscan.com/vulnerability/c2d2384c-41b9-4aaf-b918-c1cfda58af5c

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