OpenBullet2 0.3.2 NTLMv2 Hash Disclosure via UNC Path Proxy Source

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.

Problem type

Insufficiently Protected Credentials

Affected products

openbullet

openbullet2

<= 0.3.2 - AFFECTED

References

hackernoon.com

https://hackernoon.com/one-empty-header-to-admin-how-an-auth-bypass-breaks-openbullet2

technical-descriptionexploit

vulncheck.com

https://www.vulncheck.com/advisories/openbullet2-ntlmv2-hash-disclosure-via-unc-path-proxy-source

third-party-advisory

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-39908

Click to expand

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  "dataVersion": "5.2",
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    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "dateUpdated": "2026-06-08T18:06:43.929Z",
    "dateReserved": "2026-04-07T20:57:06.209Z",
    "datePublished": "2026-06-08T16:47:18.702Z",
    "state": "PUBLISHED"
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      },
      "datePublic": "2026-06-05T00:00:00.000Z",
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      "descriptions": [
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          "value": "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."
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            "privilegesRequired": "LOW",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
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