# CVE-2021-39353: Easy Registration Forms <= 2.1.1 Cross-Site Request Forgery to Stored Cross-Site Scripting

> Attackers can exploit missing nonce validation to inject arbitrary scripts via CSRF, potentially leading to code execution.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 19 Nov 2021
- **Updated:** 14 Feb 2025
- **Also known as:** GHSA-9fhm-63v7-pp72

## What is CVE-2021-39353?

CVE-2021-39353 is a high-severity vulnerability in Easy Registration Forms, published on 19 Nov 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

The Easy Registration Forms WordPress plugin is vulnerable to Cross-Site Request Forgery due to missing nonce validation via the ajax_add_form function found in the ~/includes/class-form.php file which made it possible for attackers to inject arbitrary web scripts in versions up to, and including 2.1.1.

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

## Which versions are affected by CVE-2021-39353?

It affects 1 product.


Products: Easyregistrationforms Easy Registration Forms.

## How do I fix CVE-2021-39353?

No fix has been published for CVE-2021-39353 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-39353 being exploited?

There is no known exploitation of CVE-2021-39353 in the wild and no public exploit code.

## Other vulnerabilities in Easy Registration Forms

- [CVE-2020-22275](https://insights.sbomify.com/CVE-2020-22275/): Code injection in n/a (high 8.8)
- [CVE-2023-5134](https://insights.sbomify.com/CVE-2023-5134/): Easy Registration Forms <= 2.1.1 - Authenticated (Subscriber+) Information Disclosure via Shortcode (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-39353 and fix it if it is affected.

What it is: CVE-2021-39353 is a high-severity vulnerability in Easy Registration Forms, published on 19 Nov 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-39353 in the wild and no public exploit code.

Affected product: Easy Registration Forms. 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-2021-39353/ (Markdown: https://insights.sbomify.com/CVE-2021-39353/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-39353
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-39353
- OSV: https://osv.dev/vulnerability/CVE-2021-39353

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-39353/
Summaries are generated and may contain mistakes; the official description above is the record.