Description
Bypass vulnerability in the authentication method in the GTT Tax Information System application, related to the Active Directory (LDAP) login method. Authentication is performed through a local WebSocket, but the web application does not properly validate the authenticity or origin of the data received, allowing an attacker with access to the local machine or internal network to impersonate the legitimate WebSocket and inject manipulated information. Exploiting this vulnerability could allow an attacker to authenticate as any user in the domain, without the need for valid credentials, compromising the confidentiality, integrity, and availability of the application and its data.
References1
Metrics
- CVSS 4.0
-
9.3
CRITICAL
Score source: CNA
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 41 · as of 11 November 2026
- CWE
- CWE-290
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