CVE-2026-1051

Newsletter – Send awesome emails from WordPress <= 9.1.0 - Cross-Site Request Forgery to Newsletter Unsubscription

2026-01-19 11:44

Strategic Overview

Status: Patched in 9.1.1
Affected Plugin: Newsletter – Send awesome emails from WordPress
Affected Version: <= 9.1.0
CVSS: 4.3Medium
Weakness type: CWE-352 · Cross-Site Request Forgery (CSRF)
CVE: CVE-2026-1051

View all Newsletter – Send awesome emails from WordPress vulnerabilities

At a glance

CVE-2026-1051 is a medium-severity Cross-Site Request Forgery (CSRF) vulnerability in the Newsletter WordPress plugin, affecting versions <= 9.1.0. It carries a CVSS score of 4.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 9.1.1; sites on affected versions should update now. Disclosed January 2026, reported by Sergej Ljubojevic.

Vulnerability Overview

The Newsletter – Send awesome emails from WordPress plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 9.1.0. This is due to missing or incorrect nonce validation on the hook_newsletter_action() function. This makes it possible for unauthenticated attackers to unsubscribe newsletter subscribers via a forged request granted they can trick a logged-in user into performing an action such as clicking on a link.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site.

CWE-352: Cross-Site Request Forgery (CSRF)

Newsletter <= 9.1.0 carries this weakness at hook_newsletter_action(), and reaching it takes a caller who can reach the endpoint. Cross-site request forgery abuses the fact that browsers attach a victim's cookies to any request, so a state-changing action that only checks who you are, not whether you meant to act, can be triggered from another site.

An attacker who gets a logged-in user to load a crafted page can perform that action as them, with the impact scaling to whatever the victim's role is allowed to do. For Newsletter the fix is 9.1.1: builds <= 9.1.0 are affected, anything from 9.1.1 onward is not.

Remediation

Update to version 9.1.1, or a newer patched version

How does WordSec protect against this?

The attempt arrives as an ordinary request to Newsletter: WordSec's web application firewall inspects request payloads before WordPress loads them. None of that substitutes for the fix: Newsletter 9.1.1 closes this, and updating the plugin is the step that ends it.

Firewall
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-1051 https://www.wordfence.com/threat-intel/vulnerabilities/id/8de2156f-5087-4c16-8e5d-93b5c72ec536 https://nvd.nist.gov/vuln/detail/CVE-2026-1051

Related records

Same weakness class

Other vulnerabilities in Newsletter – Send awesome emails from WordPress

CVSS Vector

4.3

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityNone
IntegrityLow
AvailabilityNone

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