Missing Authentication in OpenBMB XAgent ShareServer WebSocket Endpoint
CVE-2026-4959

6.9MEDIUM

Key Information:

Vendor

Openbmb

Status
Xagent
Vendor
CVE Published:
27 March 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-4959?

A vulnerability exists in OpenBMB XAgent 1.0.0 that allows unauthenticated users to exploit the ShareServer WebSocket Endpoint. The flaw is located in the 'check_user' function of the 'XAgentServer/application/websockets/share.py' file, where manipulation of the 'interaction_id' argument can bypass required authentication measures. This could facilitate remote exploitation and poses a significant security risk, as the exploit has been publicly disclosed. Despite early notifications to the vendor, no action has been taken to address the vulnerability.

Affected Version(s)

XAgent 1.0.0

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-4959 - Proof of Concept

References

https://vuldb.com/?id.353836
vdb-entrytechnical-description
https://vuldb.com/?ctiid.353836
signaturepermissions-required
https://vuldb.com/?submit.777622
third-party-advisory

CVSS V4

Score:
6.9
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Eric-z (VulDB User)
VulDB
.