Use of Single-factor Authentication in WS_FTP - CVE-2026-90862
Published: October 29, 2026
Vulnerability identifier: #VU158507
CSH Severity: Low
CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-90862
CWE-ID: CWE-308
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to bypass multi-factor authentication and potentially access files in the affected account.
The vulnerability exists due to reliance on single-factor authentication in the Web Transfer Module of Progress WS_FTP Server when enforcing multi-factor verification. A remote user can exploit the affected authentication flow under specific conditions to access account files without completing the additional authentication factor.
Affected software
WS_FTP
How to mitigate CVE-2026-90862
Install security update from vendor's website.
WS_FTP - addressed in versions 9.0.7, 10.0.4