CVE-2026-59804

Midscene Bridge Server - Session Hijack via Unauthenticated WebSocket

MEDIUM
6.8
CVSS Score
Published: July 8, 2026 at 07:42 PM UTC
Updated: October 25, 2026 at 05:10 PM UTC
1 product affected across 1 vendorMidscene

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Severity
MEDIUM6.8
Exploit prediction
EPSS 0.3%
SSVC
PoC

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

0 ≤ v ≤ 1.10.30
Vendor states this is fixed in 86f4118d1d847041c63d79e347e08c87c3f1a882 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.8MEDIUMVulnCheck
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-1385CWE-306

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