Bug 2567473 (CVE-2026-119744)

Summary: CVE-2026-119744 thinlinc: ThinLinc: Privilege escalation via multi-step authentication bypass
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in ThinLinc. The browser-based web client fails to properly validate authentication state during multi-step login procedures, such as one-time password prompts or login notices. An authenticated attacker can exploit this flaw to bypass authentication controls and impersonate any user, allowing them to gain unauthorized administrative access to the system.
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Description OSIDB Bzimport 2026-11-05 22:00:43 UTC
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.