CVE-2002-1291
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 Microsoft Java implementation, as used in Internet Explorer, allows remote attackers to read arbitrary local files and network shares via an applet tag with a codebase set to a "file://%00" (null character) URL.
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 Microsoft Java implementation in Internet Explorer contains a vulnerability where an applet tag with a codebase attribute set to 'file://%00' (file URL with null character) allows remote attackers to bypass security restrictions and read arbitrary local files and network shares on the victim's system.
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= 1.1CVSS 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.
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Check if Microsoft Java VM is installedOpen Control Panel > Add/Remove Programs, look for 'Microsoft Java Virtual Machine' or check registry key HKLM\SOFTWARE\Microsoft\Java VMAffected if Microsoft Java Virtual Machine is present in the system
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Verify the Microsoft Java VM version is 1.1Run 'java -version' from command line if Microsoft Java VM is in PATH, or check the version string in the registry at HKLM\SOFTWARE\Microsoft\Java VM\VersionAffected if Version equals 1.1 exactly
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Confirm Java applets are enabled in Internet ExplorerIn Internet Explorer, go to Tools > Internet Options > Security > Custom Level, look for 'Script ActiveX controls marked safe for scripting' and 'Java permissions' settingsAffected if ActiveX controls and Java are set to Enabled or Prompt (not Disabled)
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Verify Internet Explorer has Microsoft Java VM registeredCheck registry keys under HKCR\.java and HKCR\clsid for entries pointing to Microsoft Java VM COM componentsAffected if IE has Microsoft Java VM registered as an active browser plugin
The system is affected if Microsoft Java VM version 1.1 is installed with Java applets enabled in Internet Explorer, allowing the file://%00 bypass to read local files.
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 dataDisable or remove the Microsoft Java VM from Internet Explorer, or migrate to a modern browser that doesn't support Java applets. Consider disabling Java content in the browser as a defense-in-depth measure.
- Consultation1.0 h
- Implementation2.0 h
- Testing1.0 h
- Review / QA1.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2002-1291 — 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-2002-1291 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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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