MailerLite – Signup forms (official) <= 1.7.21 - Missing Authorization to Authenticated (Contributor+) Form Creation and Deletion (CVE-2026-3253) | HOL Guard CVE

Medium · CVSS 4.3CVE-2026-3253

MailerLite – Signup forms (official) <= 1.7.21 - Missing Authorization to Authenticated (Contributor+) Form Creation and Deletion

Answer in brief

CVE-2026-3253 records a Medium severity (CVSS 4.3) vulnerability in MailerLite – Signup forms (official) <= 1.7.21 - Missing Authorization to Authenticated (Contributor+) Form Creation and Deletion. The current sources do not mark it as known exploited. The current feed maps mailerlite/MailerLite – Signup forms (official) (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 24, 2026Updated Sep 24, 2026Source checked Sep 24, 2026First seen by HOL Sep 24, 2026Material review Sep 24, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 4.3
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 4.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps mailerlite/MailerLite – Signup forms (official) (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
mailerlite/MailerLite – Signup forms (official)generic	>=0 <=1.7.21	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for mailerlite/MailerLite – Signup forms (official).
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Sep 24, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 24, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 24, 2026

Sources and claim methodology

Upstream source description

The MailerLite – Signup forms (official) plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the forms() method of the AdminController class in all versions up to, and including, 1.7.21. This makes it possible for authenticated attackers, with Contributor-level access and above, to create or delete arbitrary signup forms.

Quoted source text, attributed separately from HOL analysis.