medium CVSS 6.5 EPSS 0.32%

CVE-2024-5674·PHP vulnerability

The Newsletter - API v1 and v2 addon plugin for WordPress is vulnerable to unauthorized subscribers management due to PHP type juggling issue on the check_api_key function in all versions up to, and including, 2.4.5. This makes it possible for unauthenticated attackers to list, create or delete newsletter subscribers. This issue affects only sites running the PHP version below 8.0

Severity
medium
Software
PHP
Fixed in
2.4.6
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at 0.32% — higher than 23% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Affected versions

Until: 2.4.6

Fixed in: 2.4.6

How to fix this CVE

Upgrade the Newsletter - API WordPress plugin to version 2.4.6 or later, and ensure your PHP installation is version 8.0 or above to mitigate type juggling vulnerabilities in the API key validation logic. If you are running PHP below 8.0, either update PHP immediately or disable the Newsletter API addon until both conditions are met. This vulnerability allows unauthenticated attackers to manipulate subscriber data through improper authentication checks.

sudo dnf update php php-cli php-fpm -y

Defensia detects this vulnerability

What an exploitation attempt looks like

Sample log line indicative of exploitation attempts:

POST|GET /wp-json/newsletter/v[12]/(subscribers|newsletter) HTTP/1.1.*(?!Authorization: Bearer|X-API-Key:)

WAF mitigation (if patching is not yet possible)

Add this rule to your WAF to block exploitation attempts while you schedule the patch. 

Block unauthenticated requests to /wp-json/newsletter/v1/ and /wp-json/newsletter/v2/ endpoints that lack valid Authorization or X-API-Key headers. Implement rate limiting on API endpoints to 10 requests per minute per IP address.

How to check if you are affected

  1. Step 1: Check your PHP version by running: php --version
  2. Step 2: Log into your WordPress dashboard and navigate to Plugins > Installed Plugins to verify the Newsletter plugin version is 2.4.6 or higher
  3. Step 3: Search your web server access logs for unauthenticated requests to /wp-json/newsletter/ endpoints without valid API credentials using: grep 'wp-json/newsletter' /var/log/apache2/access.log | grep -v 'Authorization'
  4. Step 4: Verify the PHP version in your phpinfo() output matches the upgraded version from Step 1

FAQ

What is CVE-2024-5674?

This vulnerability is a PHP type juggling flaw in the Newsletter - API plugin's authentication function that allows attackers to bypass API key validation and gain unauthorized access to subscriber management operations on WordPress sites running PHP versions below 8.0.

Is CVE-2024-5674 being actively exploited?

No, this vulnerability is not currently listed on the CISA Known Exploited Vulnerabilities catalog, and no public exploit code is available at this time.

What versions of PHP are affected by CVE-2024-5674?

Only PHP versions below 8.0 are affected by this vulnerability; PHP 8.0 and later have stricter type comparison rules that prevent this class of attack.

How do I check if my server is vulnerable to CVE-2024-5674?

Run php --version to check your PHP version (if below 8.0, you are at risk) and verify your Newsletter plugin version in WordPress admin by navigating to Plugins and confirming it is 2.4.6 or newer.

Does Defensia detect CVE-2024-5674?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If PHP is installed on a monitored server, CVE-2024-5674 will appear in your dashboard with remediation steps.

Related PHP CVEs

CVE-2025-25174CVSS 10Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion') vulnerability in beeteam368 BeeTeam368 Extensions beeteam368-extensions allows PHP Local File Inclusion.This issue affects BeeTeam368 Extensions: from n/a through <= 1.9.4.
CVE-2025-47916CVSS 10Invision Community 5.0.0 before 5.0.7 allows remote code execution via crafted template strings to themeeditor.php. The issue lies within the themeeditor controller (file: /applications/core/modules/front/system/themeeditor.php), where a protected method named customCss can be invoked by unauthenticated users. This method passes the value of the content parameter to the Theme::makeProcessFunction() method; hence it is evaluated by the template engine. Accordingly, this can be exploited by unauthenticated attackers to inject and execute arbitrary PHP code by providing crafted template strings.
CVE-2024-5932CVSS 10The GiveWP – Donation Plugin and Fundraising Platform plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 3.14.1 via deserialization of untrusted input from the 'give_title' parameter. This makes it possible for unauthenticated attackers to inject a PHP Object. The additional presence of a POP chain allows attackers to execute code remotely, and to delete arbitrary files.
CVE-2025-46348CVSS 10YesWiki is a wiki system written in PHP. Prior to version 4.5.4, the request to commence a site backup can be performed and downloaded without authentication. The archives are created with a predictable filename, so a malicious user could create and download an archive without being authenticated. This could result in a malicious attacker making numerous requests to create archives and fill up the file system, or by downloading the archive which contains sensitive site information. This issue has been patched in version 4.5.4.
CVE-2026-28289CVSS 10FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. A patch bypass vulnerability for CVE-2026-27636 in FreeScout 1.8.206 and earlier allows any authenticated user with file upload permissions to achieve Remote Code Execution (RCE) on the server by uploading a malicious .htaccess file using a zero-width space character prefix to bypass the security check. The vulnerability exists in the sanitizeUploadedFileName() function in app/Http/Helper.php. The function contains a Time-of-Check to Time-of-Use (TOCTOU) flaw where the dot-prefix check occurs before sanitization removes invisible characters. This vulnerability is fixed in 1.8.207.

References

Track CVEs across your fleet automatically

Defensia scans your Linux servers and tells you exactly which ones are running vulnerable versions — including CVE-2024-5674. Free for 1 server.

Get started free