GHSA-m3m3-6gww-7gj9

### Impact

Attackers can deserialize arbitrary data on affected versions of `melisplatform/melis-cms`, and ultimately leads to the execution of arbitrary PHP code on the system. Conducting this attack does not require authentication.

Users should immediately upgrade to `melisplatform/melis-cms` >= 5.0.1.

### Patches

This issue was addressed by restricting allowed classes when deserializing user-controlled data.

### References

- https://github.com/melisplatform/melis-cms/commit/d124b2474699a679a24ec52620cadceb3d4cec11

### For more information

If you have any questions or comments about this advisory, you can contact: - The original reporters, by sending an email to vulnerability.research [at] sonarsource.com; - The maintainers, by opening an issue on this repository.