CVE-2009-3047 in Web Browser
Summary
by MITRE
Opera before 10.00, when a collapsed address bar is used, does not properly update the domain name from the previously visited site to the currently visited site, which might allow remote attackers to spoof URLs.
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Analysis
by VulDB Data Team • 03/08/2025
The vulnerability described in CVE-2009-3047 represents a critical security flaw in Opera web browsers prior to version 10.00 that specifically affects the browser's address bar functionality when operating in collapsed mode. This issue stems from the browser's improper handling of domain name updates during navigation transitions, creating a potential avenue for sophisticated phishing attacks and URL spoofing operations.
The technical flaw manifests when Opera's address bar is set to collapsed mode, a feature designed to save screen space by hiding the full URL. During navigation between websites, the browser fails to correctly update the displayed domain name from the previous site to the currently visited site. This incomplete update process leaves the address bar showing information from the prior domain while the user is actually visiting a different website, creating a misleading visual representation of the current browsing context.
This vulnerability directly relates to CWE-601, which addresses URL redirector vulnerabilities and improper URL handling in web applications and browsers. The flaw essentially creates a condition where the browser's user interface becomes inconsistent with the actual network activity, allowing attackers to exploit this discrepancy for malicious purposes. The issue particularly affects users who rely on visual cues from the address bar to verify website authenticity, as the displayed information no longer accurately reflects the current browsing session.
The operational impact of this vulnerability is significant within the context of modern web security practices and threat landscape. Attackers could leverage this flaw to create convincing phishing pages that appear to be legitimate sites, as the address bar would display the domain name from a previous legitimate visit rather than the malicious site currently being accessed. This could lead to users unknowingly entering sensitive information on fraudulent websites, as the visual deception would be particularly effective when users are accustomed to seeing familiar domain names in the address bar.
The vulnerability aligns with several tactics described in the MITRE ATT&CK framework, specifically under T1566 for credential access through phishing and T1071 for application layer protocol usage. Cyber threat actors could exploit this weakness to craft more convincing social engineering campaigns, as the browser's visual deception makes it harder for users to detect fraudulent sites. The attack vector typically involves users navigating from a legitimate site to a malicious one, where the address bar continues to display the original domain name, creating a false sense of security.
Mitigation strategies for this vulnerability include immediate browser updates to Opera version 10.00 or later, which addressed the core issue through proper domain name updating mechanisms. Security-conscious organizations should also implement comprehensive user education programs to raise awareness about the importance of verifying full URLs rather than relying solely on address bar visual cues. Additionally, browser security configurations should be reviewed to ensure that collapsed address bar features are not enabled in high-risk environments where users may be more susceptible to phishing attacks. Network monitoring solutions should also be configured to detect unusual navigation patterns that might indicate exploitation attempts, and regular security audits should verify that browser configurations comply with organizational security policies.