# CVE-2019-9787: Cross-site scripting in n/a

> Unauthenticated attackers can exploit XSS to gain admin access and execute arbitrary code via PHP file modification in WordPress.

- **Severity:** High 8.8 (`CVSS:3.0/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:** Yes
- **Published:** 14 Mar 2019
- **Updated:** 4 Aug 2024
- **Also known as:** DEBIAN-CVE-2019-9787, GHSA-vqp9-3cmr-vgcc, UBUNTU-CVE-2019-9787

## What is CVE-2019-9787?

CVE-2019-9787 is a high-severity cross-site scripting vulnerability in Wordpress Wordpress, published on 14 Mar 2019. 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

WordPress before 5.1.1 does not properly filter comment content, leading to Remote Code Execution by unauthenticated users in a default configuration. This occurs because CSRF protection is mishandled, and because Search Engine Optimization of A elements is performed incorrectly, leading to XSS. The XSS results in administrative access, which allows arbitrary changes to .php files. This is related to wp-admin/includes/ajax-actions.php and wp-includes/comment.php.

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

## Which versions are affected by CVE-2019-9787?

It affects 1 product.


Products: Wordpress Wordpress.

## How do I fix CVE-2019-9787?

Upgrade to a fixed version.

## Is CVE-2019-9787 being exploited?

There is no known exploitation of CVE-2019-9787 in the wild and no public exploit code.

Public exploit code:

- This is a recurrence of cve-2019-9787 on Wordpress and a hash-based defense. (github_poc): https://github.com/sijiahi/Wordpress_cve-2019-9787_defense
- https://github.com/rkatogit/cve-2019-9787_csrf_poc (github_poc): https://github.com/rkatogit/cve-2019-9787_csrf_poc
- CodePath Assignment for Weeks 7 & 8: CVE-2017-14719, CVE-2019-9787 & Unauthenticated Page/Post Content Modification via REST API (github_poc): https://github.com/PalmTreeForest/CodePath_Week_7-8
- Try to reproduce this issue with Docker (github_poc): https://github.com/matinciel/Wordpress_CVE-2019-9787
- Overview PoC of CSRF CVE-2019-9787 WordPress Version 5.1.1  (github_poc): https://github.com/dexXxed/CVE-2019-9787
- https://github.com/kuangting4231/mitigation-cve-2019-9787 (github_poc): https://github.com/kuangting4231/mitigation-cve-2019-9787

## Other vulnerabilities in Wordpress Wordpress

- [CVE-2026-63030](https://insights.sbomify.com/CVE-2026-63030/): WordPress Core Interpretation Conflict (critical 9.8, exploited in the wild)
- [CVE-2026-87902](https://insights.sbomify.com/CVE-2026-87902/): WordPress Core Remote File Inclusion (high 8.1, exploited in the wild)
- [CVE-2026-60137](https://insights.sbomify.com/CVE-2026-60137/): WordPress Core SQL Injection (medium 5.9, exploited in the wild)
- [CVE-2012-2399](https://insights.sbomify.com/CVE-2012-2399/): Cross-site scripting in n/a (critical 10.0)
- [CVE-2012-2400](https://insights.sbomify.com/CVE-2012-2400/): Other in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-9787 and fix it if it is affected.

What it is: CVE-2019-9787 is a high-severity cross-site scripting vulnerability in Wordpress Wordpress, published on 14 Mar 2019. 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-2019-9787 in the wild and no public exploit code.

Affected product: Wordpress Wordpress. 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-2019-9787/ (Markdown: https://insights.sbomify.com/CVE-2019-9787/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-9787
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-9787
- OSV: https://osv.dev/vulnerability/CVE-2019-9787

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-9787/
Summaries are generated and may contain mistakes; the official description above is the record.