Nginx UI is a web user interface for the Nginx web server. Prior to version 2.3.5, all WebSocket endpoints in nginx-ui use a gorilla/websocket Upgrader with CheckOrigin unconditionally returning true, allowing Cross-Site WebSocket Hijacking (CSWSH). Combined with the fact that authentication tokens are stored in browser cookies (set via JavaScript without HttpOnly or explicit SameSite attributes), a malicious webpage can establish authenticated WebSocket connections to the nginx-ui instance when a logged-in administrator visits the attacker-controlled page. Version 2.3.5 patches the issue.
Metrics
Affected Vendors & Products
References
History
Mon, 20 Apr 2026 22:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
0xjacky
0xjacky nginx-ui |
|
| Vendors & Products |
0xjacky
0xjacky nginx-ui |
Mon, 20 Apr 2026 21:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Nginx UI is a web user interface for the Nginx web server. Prior to version 2.3.5, all WebSocket endpoints in nginx-ui use a gorilla/websocket Upgrader with CheckOrigin unconditionally returning true, allowing Cross-Site WebSocket Hijacking (CSWSH). Combined with the fact that authentication tokens are stored in browser cookies (set via JavaScript without HttpOnly or explicit SameSite attributes), a malicious webpage can establish authenticated WebSocket connections to the nginx-ui instance when a logged-in administrator visits the attacker-controlled page. Version 2.3.5 patches the issue. | |
| Title | Nginx-UI vulnerable to Cross-Site WebSocket Hijacking (CSWSH) via missing origin validation on all WebSocket endpoints | |
| Weaknesses | CWE-1385 | |
| References |
| |
| Metrics |
cvssV4_0
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Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-04-20T20:16:47.597Z
Updated: 2026-04-20T20:16:47.597Z
Reserved: 2026-03-27T13:45:29.620Z
Link: CVE-2026-34403
No data.
Status : Received
Published: 2026-04-20T21:16:36.267
Modified: 2026-04-20T21:16:36.267
Link: CVE-2026-34403
No data.