CVE-2026-39908

OpenBullet2 through version 0.3.2 on Windows contains a credential disclosure vulnerability that allows remote attackers to capture the NTLMv2 hash of the process user by configuring a job proxy source with a UNC path pointing to an attacker-controlled server. When the job starts, the application attempts to load proxies from the UNC path, triggering an SMB authentication attempt that discloses the NTLMv2 hash, which can then be relayed or cracked offline.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://hackernoon.com/one-empty-header-to-admin-how-an-auth-bypass-breaks-openbullet2
https://www.vulncheck.com/advisories/openbullet2-ntlmv2-hash-disclosure-via-unc-path-proxy-source

Configurations

No configuration.

History

23 Jul 2026, 07:10

Type	Values Removed	Values Added
Summary		(es) OpenBullet2 hasta la versión 0.3.2 en Windows contiene una vulnerabilidad de divulgación de credenciales que permite a atacantes remotos capturar el hash NTLMv2 del usuario del proceso al configurar una fuente de proxy de trabajo con una ruta UNC que apunta a un servidor controlado por el atacante. Cuando el trabajo se inicia, la aplicación intenta cargar proxies desde la ruta UNC, desencadenando un intento de autenticación SMB que divulga el hash NTLMv2, el cual puede ser luego retransmitido o descifrado sin conexión.

08 Jun 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-08 17:16

Updated : 2026-07-23 07:10

NVD link : CVE-2026-39908

Mitre link : CVE-2026-39908

CVE.ORG link : CVE-2026-39908

JSON object : View

Products Affected

No product.

CWE

CWE-522

Insufficiently Protected Credentials

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