CVE Catalog

CVE-2026-103482

MediumCVSS 5.4
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.31%

22th percentile - higher than 22% of all known CVEs

Summary

The Simple Newsletter Plugin – Noptin for WordPress up to version 4.3.10 is vulnerable to stored XSS via the 'noptin_fields[<custom_field_merge_tag>]' parameter. The attack requires a published campaign with a [[subscriber.*]] merge tag and uses the manage_preferences form.

Risk Assessment

Unauthenticated attackers can inject malicious scripts that execute for users visiting affected pages, potentially leading to data theft or session hijacking.

Recommendation

Update the Noptin plugin to the latest version. Limit the use of merge tags in campaigns and educate users about the risk of clicking suspicious links.

Related vulnerabilities

Original NVD description (English source)

The Simple Newsletter Plugin – Noptin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'noptin_fields[<custom_field_merge_tag>] (e.g. first_name)' parameter in all versions up to, and including, 4.3.10 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The attack chain requires a published campaign post whose body contains a [[subscriber.*]] merge tag; the unauthenticated attacker first POSTs the entity-encoded payload to the public manage_preferences form (which issues its own nonce on the same page), then pivots execution by embedding their confirm_key in a campaign preview URL sent to a privileged user via social engineering.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS