CVE-2023-53933
Serendipity 2.4.0 contains a remote code execution vulnerability that allows authenticated attackers to upload malicious PHP files with .phar extension.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.02%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 4.0
- 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/M
- EPSS
- 1.02% probability · 63th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-434
- Affected
- s9y/serendipity
- Source
- disclosure@vulncheck.com
EPSS 1.0% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://docs.s9y.org/Product
- https://www.exploit-db.com/exploits/51372Exploit, Third Party Advisory, VDB Entry
- https://www.vulncheck.com/advisories/serendipity-authenticated-remote-code-execution-via-file-uploadExploit, Third Party Advisory
- https://www.exploit-db.com/exploits/51372Exploit, Third Party Advisory, VDB Entry
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.