The All in One SEO – Best WordPress SEO Plugin – Easily Improve Your SEO Rankings before 4.1.0.2 enables authenticated users with aioseo_tools_settings privilege (most of the time admin) to execute arbitrary code on the underlying host. Users can restore plugins configuration by uploading a backup .ini file in the section Tool > Import/Export. However, the plugin attempts to unserialize values of the .ini file. Moreover, the plugin embeds Monolog library which can be used to craft a gadget chain and thus trigger system command execution.
Weakness
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| All_in_one_seo | Aioseo | * | 4.1.0.2 (excluding) |
Potential Mitigations
- Make fields transient to protect them from deserialization.
- An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.