Cotonti 1.0.0 (master branch, commit f43f1fc3) is vulnerable to Cross-Site Request Forgery in the Personal File Storage (PFS) module. In modules/pfs/inc/pfs.main.php, the file upload action ('a=upload') processes uploaded files without calling cot_check_xg() to validate the anti-CSRF token, even though sibling actions such as 'delete' (line 272) do. A remote attacker who lures an authenticated user into visiting a malicious page can force the browser to submit a forged multipart request that uploads arbitrary files into the victim's PFS storage.
Exploitability
AV:NAC:LAT:NPR:NUI:PVulnerable System
VC:HVI:HVA:NSubsequent System
SC:NSI:NSA:N8.6/CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NAuthentication