CVE-2011-1337 in Web Browser
Summary
by MITRE
Opera before 11.50 allows remote attackers to cause a denial of service (disk consumption) via invalid URLs that trigger creation of error pages.
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Analysis
by VulDB Data Team • 01/15/2025
The vulnerability identified as CVE-2011-1337 represents a denial of service flaw affecting Opera web browsers prior to version 11.50. This issue stems from the browser's handling of malformed or invalid URLs that trigger the creation of error pages, leading to excessive disk space consumption. The flaw demonstrates how seemingly benign user input can be exploited to cause significant system resource exhaustion, particularly impacting storage availability on affected systems.
The technical implementation of this vulnerability occurs when Opera processes invalid URLs that do not conform to standard web protocols or syntax. When such malformed URLs are encountered, the browser attempts to generate error pages to inform users of the invalid request. However, the error handling mechanism fails to properly validate or limit the resources consumed during error page generation, resulting in continuous disk space utilization. This behavior can be triggered remotely through web content, making it particularly dangerous in web browsing environments where users may encounter maliciously crafted URLs.
From an operational perspective, this vulnerability poses a substantial risk to system availability and user experience. Attackers can remotely consume disk space on target systems by directing users to specific malformed URLs, potentially leading to complete system unresponsiveness when storage capacity is exhausted. The impact extends beyond simple service disruption to include potential system crashes, application instability, and the requirement for manual intervention to recover affected systems. This type of resource exhaustion attack represents a classic denial of service vector that can be particularly effective against systems with limited storage capacity or those operating in constrained environments.
The vulnerability aligns with CWE-400, which categorizes "Uncontrolled Resource Consumption" as a common weakness in software systems. This classification emphasizes the lack of proper resource management and validation controls within the browser's error handling mechanism. From an adversarial perspective, this flaw fits within the ATT&CK framework under the technique of "Resource Exhaustion" (T1499), where attackers consume system resources to prevent normal operations. The remote nature of the attack means that users need not be directly involved in the exploitation process, as simply visiting a malicious website containing the crafted URL can trigger the vulnerability.
Mitigation strategies for CVE-2011-1337 primarily involve upgrading to Opera version 11.50 or later, which includes proper bounds checking and resource management for error page generation. System administrators should also implement web filtering solutions to block access to known malicious URLs and consider implementing disk space monitoring to detect unusual consumption patterns. Additionally, browser security configurations should be reviewed to ensure proper handling of malformed input, and regular security updates should be applied to maintain protection against similar vulnerabilities in the browser ecosystem.