CVE-2001-1539 in Internet Explorer
Summary
by MITRE
Stack consumption vulnerability in Internet Explorer The JavaScript settimeout function in Internet Explorer allows remote attackers to cause a denial of service (crash) via the JavaScript settimeout function. NOTE: the vendor could not reproduce the problem.
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Analysis
by VulDB Data Team • 04/07/2017
The vulnerability identified as CVE-2001-1539 represents a stack consumption issue within Microsoft Internet Explorer's JavaScript engine, specifically affecting the setTimeout function implementation. This flaw manifests as a denial of service condition that can be triggered remotely through malicious JavaScript code execution. The vulnerability resides in the browser's handling of asynchronous JavaScript execution mechanisms, where improper stack management during timeout operations leads to system instability and potential application crashes. Security researchers have classified this issue as a stack-based buffer overflow or consumption vulnerability, which falls under the broader category of memory corruption flaws that have historically been exploited for both denial of service and potentially more severe attacks.
The technical implementation of this vulnerability stems from how Internet Explorer's JavaScript engine manages the call stack when processing setTimeout function calls. When malicious JavaScript code repeatedly invokes setTimeout with specific parameters or in particular sequences, the browser's JavaScript engine consumes excessive stack memory resources without proper bounds checking or stack overflow protection mechanisms. This behavior creates a scenario where the application's stack space becomes exhausted, leading to unpredictable application termination and system instability. The vulnerability demonstrates poor resource management practices in the browser's JavaScript interpreter, where the stack consumption is not properly monitored or limited, allowing attackers to exhaust available stack memory through carefully crafted malicious scripts.
From an operational impact perspective, this vulnerability presents significant risks to users of Internet Explorer 6.0 and earlier versions, particularly in enterprise environments where browser stability is critical. The remote exploitation capability means that attackers can deliver malicious content through web pages, email attachments, or other attack vectors without requiring local system access. When successfully exploited, the vulnerability causes Internet Explorer to crash, potentially resulting in loss of unsaved work, session disruption, and forced browser restarts. Organizations may experience productivity losses and increased support overhead as users encounter frequent browser crashes. The vulnerability also represents a potential gateway for more sophisticated attacks, as initial denial of service conditions can be used as precursors to establish footholds within target networks or to disrupt business operations through persistent service interruptions.
Mitigation strategies for CVE-2001-1539 should focus on immediate remediation through official Microsoft security updates and patches that address the stack consumption issue in the JavaScript engine. Organizations should implement browser hardening measures including disabling JavaScript when not required, implementing content filtering solutions, and deploying network-based intrusion detection systems to monitor for suspicious JavaScript activity. Security teams should consider implementing application whitelisting policies that restrict execution of potentially malicious scripts and establish network segmentation to limit the impact of successful exploitation attempts. The vulnerability aligns with CWE-129, which describes improper validation of array indices, and relates to ATT&CK technique T1059.007 for JavaScript-based execution, highlighting the importance of proper input validation and execution environment hardening. Regular security assessments and penetration testing should be conducted to identify similar stack consumption vulnerabilities in other browser components and ensure comprehensive protection against similar threats that may arise from improper memory management in web browsers.