CVE-2026-103424 Cross-site scripting in Anti-Spam by CleanTalk – Spam Protection Without CAPTCHA
Unauthenticated attackers can inject arbitrary scripts via comments, leading to code execution when approved comments are viewed by site visitors.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-103424?
CVE-2026-103424 is a medium-severity cross-site scripting vulnerability in Anti-Spam by CleanTalk – Spam Protection Without CAPTCHA, published on 10 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The Anti-Spam by CleanTalk – Spam Protection Without CAPTCHA plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'comment' parameter in all versions up to, and including, 6.88 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. This vulnerability is exploitable once a comment from the attacker's email address has been approved; on default WordPress installations, only the first comment from a given email address is held for moderation, meaning subsequent comments auto-approve and immediately expose the payload to site visitors.
Weakness: CWE-79
Which versions are affected by CVE-2026-103424?
How do I fix CVE-2026-103424?
No fix has been published for CVE-2026-103424 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-103424 being exploited?
There is no known exploitation of CVE-2026-103424 in the wild and no public exploit code.
Sources
Also known as GHSA-xx63-6r6g-3hcj.