CVE-2009-0419
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 · uneditedMicrosoft XML Core Services, as used in Microsoft Expression Web, Office, Internet Explorer 6 and 7, and other products, does not properly restrict access from web pages to Set-Cookie2 HTTP response headers, which allows remote attackers to obtain sensitive information from cookies via XMLHttpRequest calls, related to the HTTPOnly protection mechanism. NOTE: this issue reportedly exists because of an incomplete fix for CVE-2008-4033.
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 · moderate confidenceMicrosoft XML Core Services (MSXML) fails to properly restrict XMLHttpRequest access to Set-Cookie2 HTTP response headers, allowing remote attackers to bypass the HTTPOnly cookie protection mechanism and obtain sensitive information from cookies. This vulnerability exists because of an incomplete fix for the prior CVE-2008-4033, affecting Expression Web, Office, Internet Explorer 6/7, and other Microsoft products using MSXML.
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 dataall versionsCVSS 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
- Authentication
- None
- Confidentiality
- Partial
- Integrity
- None
- Availability
- None
AV:N/AC:L/Au:N/C:P/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.
-
Check Internet Explorer versionOpen Internet Explorer, click Help > About Internet Explorer, or run 'winver' command to see IE versionAffected if Version is 6.0 or 7.x (these are the affected versions)
-
Identify installed MSXML versionsCheck registry key HKEY_CLASSES_ROOT\MSXML version folders, or use PowerShell: Get-ItemProperty 'HKLM:\SOFTWARE\Classes\TypeLib\{F5078F18-C551-11D3-89B9-0000F81FE221}' -ErrorAction SilentlyContinueAffected if Any version of MSXML is present on the system (all versions are affected)
-
Check for applications using MSXMLSearch for .xml files processed by web applications, or check application logs for MSXML parser usage. Look for applications that make XMLHttpRequest callsAffected if Applications use XMLHttpRequest to process responses containing Set-Cookie2 headers
-
Verify HTTPOnly cookie handlingInspect cookies received via XMLHttpRequest in affected applications. If Set-Cookie2 headers are accessible via response headers in JavaScript, the bypass is presentAffected if XMLHttpRequest can read Set-Cookie2 headers that should be protected by HTTPOnly attribute
System is affected if running Internet Explorer 6/7, or if any MSXML version is installed and processes XML content with cookies, since the HTTPOnly protection can be bypassed via Set-Cookie2 header access.
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 security patches for MSXML when available; upgrade affected systems from Internet Explorer 6/7 to newer versions; consider implementing additional session security measures since HTTPOnly protection cannot be relied upon.
- Consultation4.0 h
- Implementation2.0 h
- Testing3.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,864.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2009-0419 — 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-2009-0419 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
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- 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