CVE-2023-53956 Flatnux 2021-03.25 Authenticated File Upload Remote Code Execution
Administrative users can upload arbitrary PHP files to the web root, enabling remote code execution on the server.
- 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-2023-53956?
CVE-2023-53956 is a high-severity vulnerability in altervista flatnux, published on 19 Dec 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Flatnux 2021-03.25 contains an authenticated file upload vulnerability that allows administrative users to upload arbitrary PHP files through the file manager. Attackers with admin credentials can upload malicious PHP scripts to the web root directory, enabling remote code execution on the server.
Weakness: CWE-434
Which versions are affected by CVE-2023-53956?
How do I fix CVE-2023-53956?
No fix has been published for CVE-2023-53956 yet. Limit exposure of the affected software until one is available.
Is CVE-2023-53956 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-53956 exists.
Sources
Also known as GHSA-r9qg-6q9c-jpvx.