CVE-2010-5248
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedUntrusted search path vulnerability in UltraVNC 1.0.8.2 allows local users to gain privileges via a Trojan horse vnclang.dll file in the current working directory, as demonstrated by a directory that contains a .vnc file. NOTE: some of these details are obtained from third party information.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceUltraVNC 1.0.8.2 contains an untrusted search path vulnerability where the application loads the vnclang.dll library from the current working directory instead of only from trusted system paths. When a user opens a .vnc file from a directory containing a malicious vnclang.dll, the application will execute the trojaned library, allowing local privilege escalation.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data= 1.0.8.2CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- M
- Authentication
- None
- Confidentiality
- Complete
- Integrity
- Complete
- Availability
- Complete
AV:L/AC:M/Au:N/C:C/I:C/A:C
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Verify UltraVNC version is 1.0.8.2Check the installed UltraVNC version by examining the winvnc.exe file properties (right-click > Properties > Details > File Version) or check the registry key HKLM\SOFTWARE\UltraVNC for the InstallPath, then locate and inspect the executableAffected if The installed version is exactly 1.0.8.2
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Confirm vnclang.dll is present in UltraVNC directoryNavigate to the UltraVNC installation folder (commonly C:\Program Files\UltraVNC or C:\Program Files (x86)\UltraVNC) and verify that vnclang.dll exists in that directoryAffected if vnclang.dll exists in the UltraVNC program directory (the application uses this DLL which can be loaded from an untrusted path)
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Check for DLL in user-accessible directoriesSearch the filesystem for any vnclang.dll files in user-writable directories such as Downloads, Documents, Desktop, or shared/network foldersAffected if A vnclang.dll exists in a directory where a .vnc file might be opened (the application loads this DLL from the current working directory when opening a .vnc file)
A user is affected if UltraVNC 1.0.8.2 is installed and a vnclang.dll exists in any directory from which they might open .vnc files, allowing DLL hijacking from the current working directory.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataUpdate to a patched version of UltraVNC that implements safe DLL loading by using full paths or disabling DLL search path traversal to current directory. Users should avoid opening .vnc files from untrusted or shared directories.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2010-5248 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2010-5248 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data