CVE-2011-4681: Opera before 11.60 does not properly consider the number of .

Security readout for executives and security teams

Older Opera versions before 11.60 could confuse which sites should be isolated from each other on multi-part country domains such as .uk or .no. A malicious site in the same top-level domain could potentially cross browser boundaries that should be enforced. This is mainly a legacy browser risk. Exposure is most likely where legacy Opera browsers before 11.60 remain installed, embedded, or supported. Modern environments are unlikely to be affected unless old browser builds are retained for compatibility testing, kiosks, virtual desktops, or unmanaged endpoints. Treat as a targeted legacy cleanup item, not an emergency absent evidence of active exploitation. Prioritize organizations with unmanaged endpoints, legacy browser dependencies, or sensitive applications accessed through old Opera versions. Mitigation focus: Upgrade Opera installations before 11.60 to 11.60 or later.; Remove unsupported legacy Opera builds from managed endpoints and images.; Check Opera vendor guidance for platform-specific update details..

Prepared

Jun 27, 2026, 17:48 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.