# CVE-2026-78175: Tutor LMS <= 4.0.7 - Authenticated (Subscriber+) PHP Object Injection to Remote Code Execution

> Authenticated attackers can achieve remote code execution via PHP object injection in Tutor LMS when monetization is enabled.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 12 Sep 2026
- **Updated:** 15 Sep 2026
- **Also known as:** GHSA-cg5c-mg8j-jqc2

## What is CVE-2026-78175?

CVE-2026-78175 is a high-severity unsafe deserialization vulnerability in themeum Tutor LMS – eLearning and online course solution, published on 12 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The Tutor LMS – eLearning and online course solution plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 4.0.7 via the `withdraw_method_field` parameter of the `tutor_save_withdraw_account` AJAX handler. This is due to the handler lacking any capability or role check, relying solely on a nonce, while also passing attacker-supplied values through `esc_sql()`, which replaces every `%` character with a 66-byte HMAC placeholder token before the data is serialized and stored via `update_user_meta()`; when the meta is later retrieved, the placeholder is collapsed back to a single `%`, leaving serialized string length declarations 65 bytes greater than the actual content, and because array keys originate from entirely unescaped POST field names, `unserialize()` over-reads into attacker-controlled bytes, allowing injection of an arbitrary serialized object stream. This makes it possible for authenticated attackers, with subscriber-level access and above, to achieve remote code execution on the server by triggering the `GuzzleHttp\Cookie\FileCookieJar` POP chain, reachable via the `spl_autoload_register` loader in `TUTOR\RestAPI` which loads the plugin's own bundled PayPal Composer autoloader, writing attacker-controlled content to an attacker-specified filename. This has an unauthenticated pathway when user registration is enabled, which is common for students and teachers to register, and it requires the monetization feature to be enabled.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2026-78175?


## How do I fix CVE-2026-78175?

No fix has been published for CVE-2026-78175 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-78175 being exploited?

There is no known exploitation of CVE-2026-78175 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-78175 and fix it if it is affected.

What it is: CVE-2026-78175 is a high-severity unsafe deserialization vulnerability in themeum Tutor LMS – eLearning and online course solution, published on 12 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-78175 in the wild and no public exploit code.

Affected product: themeum Tutor LMS – eLearning and online course solution. 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-2026-78175/ (Markdown: https://insights.sbomify.com/CVE-2026-78175/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-78175
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-78175
- OSV: https://osv.dev/vulnerability/CVE-2026-78175

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-78175/
Summaries are generated and may contain mistakes; the official description above is the record.