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.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
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
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.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-78175 being exploited?
There is no known exploitation of CVE-2026-78175 in the wild and no public exploit code.
Sources
Also known as GHSA-cg5c-mg8j-jqc2.