CVE-2009-0771 in Firefox
Summary
by MITRE
The layout engine in Mozilla Firefox before 3.0.7, Thunderbird before 2.0.0.21, and SeaMonkey 1.1.15 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via certain vectors that trigger memory corruption and assertion failures.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 08/30/2019
The vulnerability identified as CVE-2009-0771 represents a critical memory corruption flaw affecting the layout engine components of several Mozilla-based applications. This issue specifically impacts Firefox versions prior to 3.0.7, Thunderbird versions prior to 2.0.0.21, and SeaMonkey version 1.1.15, creating a significant attack surface for malicious actors seeking to exploit these applications. The flaw manifests through specific vectors that trigger assertion failures within the browser's rendering engine, potentially leading to system instability and unauthorized code execution.
The technical nature of this vulnerability stems from improper memory management within the layout engine's handling of certain web content structures. When processing malformed or specially crafted HTML elements, the affected applications fail to properly validate memory allocations, resulting in memory corruption conditions that can be exploited to trigger crashes or potentially gain remote code execution capabilities. This type of vulnerability aligns with CWE-125, which describes out-of-bounds read conditions, and CWE-787, which covers out-of-bounds write vulnerabilities that can lead to memory corruption.
From an operational perspective, this vulnerability presents a substantial risk to organizations relying on these older versions of Mozilla applications, as it enables remote attackers to cause denial of service conditions that can crash applications and potentially allow arbitrary code execution. The attack vectors typically involve visiting malicious web pages or receiving specially crafted emails that contain malformed content designed to trigger the memory corruption. According to ATT&CK framework, this vulnerability maps to T1203, which covers Exploitation for Client Execution, and T1499, covering Network Denial of Service.
The impact extends beyond simple application crashes, as successful exploitation can provide attackers with the ability to execute arbitrary code on affected systems, potentially leading to complete system compromise. This vulnerability particularly affects environments where users may encounter untrusted web content or email messages, making it a significant concern for enterprise security teams. Organizations running these vulnerable versions face increased risk of data breaches, system compromise, and service disruption. The memory corruption nature of the flaw makes it particularly dangerous as it can be difficult to detect and may leave persistent system vulnerabilities that can be leveraged for further attacks.
Mitigation strategies should prioritize immediate patching of all affected versions to prevent exploitation. Security administrators should implement network segmentation and web filtering to limit exposure to potentially malicious content. Additionally, user education regarding safe browsing practices and email handling can help reduce the risk of successful exploitation. Regular security assessments and vulnerability scanning should be conducted to identify any remaining instances of vulnerable software within the organization's infrastructure. The remediation process should also include monitoring for any signs of exploitation attempts and implementing proper incident response procedures to address potential compromise.