# CVE-2026-120019: The W3 Total Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'comment' parameter in all versions up to, and


- **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
- **Fix available:** No
- **Published:** 31 Oct 2026
- **Updated:** 1 Nov 2026
- **Also known as:** GHSA-59h3-w5qx-76fv

## What is CVE-2026-120019?

CVE-2026-120019 is a medium-severity vulnerability in boldgrid W3 Total Cache, published on 31 Oct 2026. 

### Official description

The W3 Total Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'comment' parameter in all versions up to, and including, 2.10.7 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 requires HTML Minify to be enabled with the default 'mfunc' entry present in the ignored-comment stems list, and exploitation depends on the attacker predicting the md5(time()) placeholder namespace by reading the server clock via the HTTP Date response header within the applicable time window.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2026-120019?


## How do I fix CVE-2026-120019?

No fix has been published for CVE-2026-120019 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-120019 being exploited?

There is no known exploitation of CVE-2026-120019 in the wild and no public exploit code.

Public exploit code:

- https://github.com/Hassham1/CVE-2026-120019-w3tc-mfunc-comment-xss-poc (github_poc): https://github.com/Hassham1/CVE-2026-120019-w3tc-mfunc-comment-xss-poc

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-120019 and fix it if it is affected.

What it is: CVE-2026-120019 is a medium-severity vulnerability in boldgrid W3 Total Cache, published on 31 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-120019 in the wild and no public exploit code.

Affected product: boldgrid W3 Total Cache. 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-2026-120019/ (Markdown: https://insights.sbomify.com/CVE-2026-120019/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-120019
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-120019
- OSV: https://osv.dev/vulnerability/CVE-2026-120019

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-120019/
Summaries are generated and may contain mistakes; the official description above is the record.