Opera BrowserApplication · Opera

CVE-2011-2635

MEDIUM · 5.0 CVSS v2.0 Published 2011-07-01
Fix available
A fix is available. Upgrade to after 11.10 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
The Cascading Style Sheets (CSS) implementation in Opera before 11.10 allows remote attackers to cause a denial of service (application crash) via vectors involving use of the :hover pseudo-class, in conjunction with transforms, for a floated element.

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 confidence

A denial-of-service vulnerability in Opera browsers before version 11.10. The issue is in the CSS rendering engine where combining the :hover pseudo-class with CSS transforms on a floated (float) element triggers an application crash.

MitigationUpgrade Opera to version 11.10 or later, or migrate to a supported browser that receives security updates.

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:<= 11.10= 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
None
Integrity
None
Availability
Partial

AV:N/AC:L/Au:N/C:N/I:N/A:P

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. Identify if Opera browser is installed
    Check for Opera executable in common locations: C:\Program Files\Opera\opera.exe on Windows, /Applications/Opera.app on macOS, or run 'which opera' on Linux
    Affected if Opera browser is present on the system
  2. Determine installed Opera version
    Launch Opera, go to Help > About Opera, or check the file version of the opera.exe file by right-clicking the executable and selecting Properties > Details
    Affected if The displayed version is 11.10 or lower, or matches any of these versions: 5.0, 5.02, 5.10, 5.11, 5.12, 6.0, 6.1, 6.01, 6.02, 6.03, 6.04
  3. Inspect for vulnerable CSS configuration
    Search web application source code or HTML files for CSS rules that contain both the :hover pseudo-class combined with CSS transform properties applied to elements using the float property
    Affected if CSS rules contain a combination of :hover pseudo-class, transform property (such as transform, -webkit-transform, -moz-transform), and float property on the same element selector

The user is affected if Opera version 11.10 or lower is installed AND web content containing :hover combined with CSS transforms on floated elements is processed.

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 11.10
Interim mitigation

Upgrade Opera to version 11.10 or later, or migrate to a supported browser that receives security updates.

Fix this in Opera Browser Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $910
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,456.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2011-2635 — 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-2011-2635 in production — separate from our analysis above.

No notes yet

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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