An unauthenticated arbitrary file upload vulnerability exists in FlashChat versions 6.0.2 and 6.0.4 through 6.0.8. The upload.php endpoint fails to properly validate file types and authentication, allowing attackers to upload malicious PHP scripts. Once uploaded, these scripts can be executed remotely, resulting in arbitrary code execution as the web server user.
https://www.vulncheck.com/advisories/flashchat-arbitrary-file-upload-rce
https://www.phpbb.com/community/viewtopic.php?t=2627786
https://www.fortiguard.com/encyclopedia/ips/37342/flashchat-arbitrary-file-upload
Published: 2025-07-31
Updated: 2025-07-31
Base Score: 7.5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P
Severity: High
Base Score: 9.8
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity: Critical
Base Score: 9.3
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: Critical
EPSS: 0.00136