# 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.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 10 Oct 2026
- **Updated:** 11 Oct 2026
- **Also known as:** GHSA-xx63-6r6g-3hcj

## 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 (Improper Neutralization of Input During Web Page Generation)

## 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.

## Is CVE-2026-103424 being exploited?

There is no known exploitation of CVE-2026-103424 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-103424 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-103424 in the wild and no public exploit code.

Affected product: Anti-Spam by CleanTalk – Spam Protection Without CAPTCHA. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-103424/ (Markdown: https://insights.sbomify.com/CVE-2026-103424/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-103424
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-103424
- OSV: https://osv.dev/vulnerability/CVE-2026-103424

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-103424/
Summaries are generated and may contain mistakes; the official description above is the record.