Opera BrowserApplication · Opera

CVE-2008-4199

MEDIUM · 5.0 CVSS v2.0 Published 2008-09-27
Fix available
A fix is available. Upgrade to after 9.51 or later.
See remediation →
59/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

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 · unedited
Opera before 9.52 does not prevent use of links from web pages to feed source files on the local disk, which might allow remote attackers to determine the validity of local filenames via vectors involving "detection of JavaScript events and appropriate manipulation."

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 confidence

Opera before 9.52 failed to restrict links from web pages to feed source files on the local disk, allowing remote attackers to probe for valid local filenames by creating links to suspected file paths and detecting JavaScript events that indicate whether the target file exists.

MitigationUpgrade to Opera 9.52 or later, or migrate to a modern supported browser that has addressed similar local file enumeration risks.

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
Opera BrowserApplication
Affected:<= 9.51= 5.0= 5.02= 5.10= 5.11= 5.12= 6.0= 6.1= 6.01= 6.02= 6.03= 6.04

CVSS 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 checks

Work through these to decide whether this CVE applies to you.

  1. Locate Opera browser installation
    Search common installation paths (e.g., C:\Program Files\Opera\opera.exe, C:\Program Files (x86)\Opera\opera.exe, ~/.opera/opera on Linux) or use system search commands to find the opera executable
    Affected if Opera browser is found on the system
  2. Determine installed Opera version
    Right-click the opera.exe file and select Properties, then view the Version tab; or run 'opera --version' from command line if available
    Affected if The version displayed is 9.51 or lower, or matches one of: 5.0, 5.02, 5.10, 5.11, 5.12, 6.0, 6.1, 6.01, 6.02, 6.03, 6.04
  3. Verify JavaScript is enabled
    Open Opera, go to Settings > Preferences > Advanced > Content and check if JavaScript is enabled, or inspect the opera6.ini configuration file for JavaScript settings
    Affected if JavaScript is enabled in the browser settings (required for the attack to detect file existence via events)
  4. Confirm local file access is permitted
    Check Opera settings for allowing access to local files from web pages (Settings > Preferences > Security > Enable 'Allow pages to open windows without name' and related local file access options)
    Affected if The browser permits web pages to access local file:// URLs or feed source files

A user is affected if they have Opera version 9.51 or below (or specifically versions 5.0-6.04) installed with JavaScript enabled, as this combination allows remote probing of local filenames through malicious web pages.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 data
Upgrade available Upgrade to a release after 9.51
Interim mitigation

Upgrade to Opera 9.52 or later, or migrate to a modern supported browser that has addressed similar local file enumeration risks.

Fix this in Opera Browser Scoped from the published advisory
  • Consultation1.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
5.0 hours of engineering $860
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,376.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2008-4199 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2008-4199 in production — separate from our analysis above.

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.

What this is

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.

What belongs here
  • 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