Vulnerability · Published Jun 8, 2026 · Assigned by VulnCheck
CVE-2026-39908OpenBullet2 0.3.2 NTLMv2 Hash Disclosure via UNC Path Proxy Source
Medium 6.5
In plain English
A medium-severity security flaw in openbullet2 from openbullet. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 58% of all known vulnerabilities). Ready-made attack tooling exists: Metasploit.
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| openbullet | openbullet2 | 0 – through 0.3.2 |
Weakness: CWE-522 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
References
- https://hackernoon.com/one-empty-header-to-admin-how-an-auth-bypass-breaks-openbullet2 technical-description, exploit
- https://www.vulncheck.com/advisories/openbullet2-ntlmv2-hash-disclosure-via-unc-path-proxy-source third-party-advisory