CVE-2026-119744: Cendio ThinLinc Improper Authentication via Web Access
Cendio ThinLinc contains an improper authentication vulnerability in its browser-based web client (tlwebaccess) that allows an authenticated attacker to impersonate any other user, including root, by exploiting flaws in multi-step authentication flows such as one-time passwords, login banners, or expired password prompts. Attackers can leverage this authentication bypass during the multi-step login process to gain unauthorized access to other user accounts, including administrative privileges, in versions from 4.1.0 through 4.20.0.
Event History
Frequently Asked Questions
Who can exploit this issue?
An attacker must already be authenticated to the ThinLinc browser-based web client, tlwebaccess. No user interaction is required, and exploitation can lead to impersonation of any user, including root.
Which deployments are exposed?
ThinLinc versions from 4.1.0 through 4.20.0 are affected when the browser-based tlwebaccess client is used. The vulnerable paths involve multi-step authentication flows, including one-time passwords, login banners, and expired-password prompts.
What access can an attacker gain?
The attacker can bypass authentication flow controls to access another user's account. This includes accounts with administrative privileges and potentially the root account.