CVE-2009-3272 in Safari
Summary
by MITRE
Stack consumption vulnerability in WebKit.dll in WebKit in Apple Safari 3.2.3, and possibly other versions before 4.1.2, allows remote attackers to cause a denial of service (application crash) via JavaScript code that calls eval on a long string composed of A/ sequences.
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Analysis
by VulDB Data Team • 05/26/2025
The vulnerability identified as CVE-2009-3272 represents a stack consumption issue within the WebKit rendering engine component known as WebKit.dll that was present in Apple Safari version 3.2.3 and potentially other versions prior to 4.1.2. This flaw specifically manifests when the browser processes JavaScript code that invokes the eval function with an exceptionally long string composed of repeated A/ sequences. The technical nature of this vulnerability places it within the category of stack-based buffer overflow conditions that can lead to application instability and system crashes.
The core technical flaw involves the improper handling of stack memory allocation when processing JavaScript code through the eval function. When attackers craft malicious JavaScript that calls eval with a long string containing A/ sequences, the WebKit engine consumes excessive stack space during the parsing and execution process. This uncontrolled stack consumption eventually leads to stack exhaustion, causing the Safari browser to crash and terminate unexpectedly. The vulnerability operates at the intersection of JavaScript interpretation and memory management within the browser's rendering engine, making it particularly dangerous as it can be triggered through standard web browsing activities without requiring special privileges or user interaction beyond visiting a malicious website.
The operational impact of this vulnerability extends beyond simple application crashes to potentially enable more sophisticated attack vectors. While the immediate effect is a denial of service condition that disrupts user browsing sessions, the underlying memory management flaw could theoretically be exploited to execute arbitrary code or escalate privileges within the browser context. This vulnerability demonstrates how seemingly benign JavaScript operations can be weaponized to compromise system stability and user experience, particularly in environments where Safari serves as the primary web browser. The attack requires minimal user interaction, making it particularly concerning for widespread exploitation.
Mitigation strategies for CVE-2009-3272 primarily focus on updating to patched versions of Safari where the vulnerability has been addressed through improved stack management and input validation. Users should immediately upgrade to Safari 4.1.2 or later versions that contain the necessary security patches. Additionally, implementing browser security measures such as sandboxing, content filtering, and disabling JavaScript in untrusted environments can provide additional protection layers. Organizations should also consider deploying web application firewalls and monitoring systems that can detect and block suspicious JavaScript patterns that may indicate exploitation attempts. This vulnerability aligns with CWE-129, which addresses improper validation of array indices, and falls under ATT&CK technique T1059.007 for JavaScript execution, highlighting the importance of comprehensive browser security measures.