High 8.8Published Dec 19, 2025

CVE-2023-53956Flatnux 2021-03.25 Authenticated File Upload Remote Code Execution

Updated under an hour ago (Oct 28, 2026, 4:23 AM ET)

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Every CVE for altervista flatnux

Exploited in the last 30 days

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.

CVSS: 8.8 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-434
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Deferred
Record last updated: Apr 7, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

altervista flatnux altervista:flatnux (from the name)	2021-03.25	CNA record

References

References

https://www.exploit-db.com/exploits/51295	exploit
http://flatnux.altervista.org/flatnux.html	product
https://www.vulncheck.com/advisories/flatnux-authenticated-file-upload-remote-code-execution	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.