# CVE-2021-25094: Tatsu < 3.3.12 - Unauthenticated RCE

> Unauthenticated attackers can upload a malicious PHP shell via a zip file to achieve remote code execution on the WordPress site.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/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:** Not needed
- **Fix available:** No
- **Published:** 25 Apr 2022
- **Updated:** 21 Apr 2025
- **Also known as:** GHSA-grmv-gp4f-w59q

## What is CVE-2021-25094?

CVE-2021-25094 is a high-severity vulnerability in Unknown Tatsu, published on 25 Apr 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Tatsu WordPress plugin before 3.3.12 add_custom_font action can be used without prior authentication to upload a rogue zip file which is uncompressed under the WordPress's upload directory. By adding a PHP shell with a filename starting with a dot ".", this can bypass extension control implemented in the plugin. Moreover, there is a race condition in the zip extraction process which makes the shell file live long enough on the filesystem to be callable by an attacker.

Weakness: CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2021-25094?

It affects 1 product.


Products: Brandexponents Tatsu.

## How do I fix CVE-2021-25094?

No fix has been published for CVE-2021-25094 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-25094 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-25094 exists.

Public exploit code:

- https://github.com/darkpills/CVE-2021-25094-tatsu-preauth-rce (github_poc): https://github.com/darkpills/CVE-2021-25094-tatsu-preauth-rce
- GILANG - Exploiter for CVE-2021-25094 (github_poc): https://github.com/TUANB4DUT/typehub-exploiter
- This script exploits a vulnerability (CVE-2021-25094) in the TypeHub WordPress plugin. (github_poc): https://github.com/experimentalcrow1/TypeHub-Exploiter
- Tatsu Wordpress Plugin RCE (metasploit)
- Tatsu Plugin ZIP File add_custom_font unrestricted upload (github_poc): https://github.com/xdx57/CVE-2021-25094
- Tatsu 3.3.11 - Unauthenticated RCE (exploitdb)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-25094 and fix it if it is affected.

What it is: CVE-2021-25094 is a high-severity vulnerability in Unknown Tatsu, published on 25 Apr 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-25094 exists.

Affected product: Unknown Tatsu. 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-2021-25094/ (Markdown: https://insights.sbomify.com/CVE-2021-25094/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-25094
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-25094
- OSV: https://osv.dev/vulnerability/CVE-2021-25094

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-25094/
Summaries are generated and may contain mistakes; the official description above is the record.