CVE-2023-53933

Serendipity 2.4.0 Authenticated Remote Code Execution via File Upload

Serendipity 2.4.0 contains a remote code execution vulnerability that allows authenticated attackers to upload malicious PHP files with .phar extension. Attackers can upload files with system command payloads to the media upload endpoint and execute arbitrary commands on the server.

Affected

s9y · Serendipity

CVSS v4.0 VULNCHECK

8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CVSS v3.1 VULNCHECK

8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS

1.02% chance of exploitation in the next 30 days, 63rd percentile

Published

2025-12-17

Updated

2026-04-07

Proof-of-concept exploits (1)

• https://www.exploit-db.com/exploits/51372

Security advisories

• https://www.vulncheck.com/advisories/serendipity-authenticated-remote-code-execution-via-…
• https://docs.s9y.org

References

• CVE Record
• NVD entry