CVE-2026-59804

HIGH
MEDIUM Priority: 0.02 BB Relevance: 65/100
Published: 2026-07-08 Modified: 2026-10-25 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth Conf. Impact Integ. Impact

CVSS Vector Breakdown

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

Description

Midscene Bridge Server through 1.10.3, fixed in commit 86f4118, contains a missing authentication and CORS misconfiguration vulnerability that allows unauthenticated remote attackers to hijack active bridge sessions by opening a cross-origin WebSocket connection to the local Socket.IO server, which performs no Origin header validation and requires no authentication token. Attackers can connect from any web page visited by the victim to seize the single-client slot, intercept and inject automation commands, exfiltrate command-payload data, or unconditionally terminate the server by supplying the MIDSCENE_BRIDGE_SIGNAL_KILL query parameter.

Weakness Classification (2)

Bug Bounty Relevance

65 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

7.6 / 10.0 v4.0
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:N/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 — Exploitation Probability

0.31%
Raw Score 0.003080
Percentile 23.6%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00308
2026-10-28
0.00308

Intelligence Sources

nvd ref →