Dashboard / CVE-2026-34403

CVE-2026-34403

MEDIUM
MEDIUM Priority: 0.01 BB Relevance: 61/100
Published: 2026-04-20 Modified: 2026-10-26 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: Active
S: X
AT: None
VC: None
VI: High
VA: None

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.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
nginxui nginx_ui < 2.3.5

References & Advisories (2)

Bug Bounty Relevance

61 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

5.5 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/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 — Exploitation Probability

0.18%
Raw Score 0.001760
Percentile 7.1%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00176
2026-10-28
0.00176

Intelligence Sources

nvd ref →

External Links