CVE-2026-3787 (GCVE-0-2026-3787)

Vulnerability from cvelistv5 – Published: 2026-03-08 23:02 – Updated: 2026-03-08 23:02 X_Open Source
VLAI?
Title
UltraVNC Windows Service cryptbase.dll uncontrolled search path
Summary
A weakness has been identified in UltraVNC 1.6.4.0 on Windows. This affects an unknown function in the library cryptbase.dll of the component Windows Service. This manipulation causes uncontrolled search path. The attack requires local access. A high degree of complexity is needed for the attack. The exploitability is reported as difficult. The vendor was contacted early about this disclosure but did not respond in any way.
Severity ?
7.3 (High)
CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
7 (High)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
7 (High)
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R
CWE
Assigner
References
Impacted products
Vendor Product Version
n/a UltraVNC Affected: 1.6.4.0
    cpe:2.3:a:ultravnc:ultravnc:*:*:*:*:*:*:*:*
Credits
haehanse (VulDB User) VulDB
Show details on NVD website
To clipboard 

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          "vendor": "n/a",
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              "version": "1.6.4.0"
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        }
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          "tags": [
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          "value": "VulDB entry last update"
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      "title": "UltraVNC Windows Service cryptbase.dll uncontrolled search path"
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    "datePublished": "2026-03-08T23:02:06.940Z",
    "dateReserved": "2026-03-08T07:11:28.250Z",
    "dateUpdated": "2026-03-08T23:02:06.940Z",
    "state": "PUBLISHED"
  },
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  }
}


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Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.