CVE-2009-2495
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 · uneditedThe Active Template Library (ATL) in Microsoft Visual Studio .NET 2003 SP1, Visual Studio 2005 SP1 and 2008 Gold and SP1, and Visual C++ 2005 SP1 and 2008 Gold and SP1 does not properly enforce string termination, which allows remote attackers to obtain sensitive information via a crafted HTML document with an ATL (1) component or (2) control that triggers a buffer over-read, related to ATL headers and buffer allocation, aka "ATL Null String Vulnerability."
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 confidenceThe Active Template Library (ATL) in Microsoft Visual Studio and Visual C++ contains a flaw where string termination is not properly enforced, allowing buffer over-reads when processing crafted HTML documents with ATL components or controls. This can lead to information disclosure by reading beyond intended buffer boundaries.
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= 2005= 2008= 2005= 2008= 2003CVSS 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
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
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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Identify installed Visual Studio or Visual C++ versionOpen the IDE and go to Help > About Microsoft Visual Studio, or check Add/Remove Programs for Visual Studio entries, or check the product version in the installation directory (typically C:\Program Files\Microsoft Visual Studio [version] or C:\Program Files\Microsoft Visual C++ [version])Affected if The installed version is Visual Studio 2005, 2008, or Visual Studio .NET 2003, or Visual C++ 2005 or 2008
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Determine if ATL components or controls are deployedSearch the application deployment directory and system for compiled DLLs or controls that may use ATL (look for files with .dll, .ocx, or .ax extensions), and review application source code for #include <atlbase.h> or other ATL header includesAffected if ATL-based components or controls are present in the environment and process HTML documents from untrusted sources
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Check if vulnerable ATL headers were used during compilationInspect the ATL header files in the Visual Studio installation under Include or Atl directory (such as atlbase.h, atlcom.h, or atlwin.h) and compare file dates and versions to patched releases from Microsoft security update MS09-035Affected if The ATL header files date prior to the MS09-035 security update release and were used to compile deployed components
A user is affected if they have Visual Studio/Visual C++ 2003-2008 installed AND have deployed components or controls compiled with the original unpatched ATL headers that process HTML documents.
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 dataApply Microsoft's security updates for the affected Visual Studio and Visual C++ versions (2003 SP1, 2005 SP1, 2008 Gold/SP1). Rebuild any applications or components that were compiled with vulnerable ATL headers using the patched libraries.
- Consultation2.0 h
- Implementation4.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,328.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2009-2495 — 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-2009-2495 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
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