CVE-2011-2991 in Firefox
Summary
by MITRE
The browser engine in Mozilla Firefox 4.x through 5, SeaMonkey 2.x before 2.3, Thunderbird before 6, and possibly other products does not properly implement JavaScript, which allows remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unspecified vectors.
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Analysis
by VulDB Data Team • 11/18/2021
The vulnerability identified as CVE-2011-2991 represents a critical flaw in the JavaScript engine implementation across multiple Mozilla-based applications including Firefox 4.x through 5, SeaMonkey 2.x before 2.3, and Thunderbird before 6. This issue stems from improper JavaScript implementation that creates exploitable conditions within the browser engine's execution environment. The vulnerability manifests through unspecified vectors that can be leveraged by remote attackers to compromise system integrity and availability. The flaw specifically targets the JavaScript engine's memory management and execution mechanisms, creating opportunities for both denial of service attacks and potential code execution exploits.
The technical nature of this vulnerability aligns with CWE-119, which describes weaknesses in memory management that can lead to memory corruption issues. This classification indicates that the flaw involves improper handling of memory access patterns within the JavaScript engine, potentially allowing attackers to manipulate memory locations through crafted JavaScript code. The vulnerability's impact extends beyond simple crashes to potentially enable arbitrary code execution, making it particularly dangerous in threat landscapes where attackers seek persistent access to target systems. The memory corruption aspects of this flaw can be exploited through techniques that manipulate heap memory or stack structures during JavaScript execution, creating conditions where attacker-controlled data can overwrite critical program memory.
From an operational perspective, this vulnerability presents significant risks to organizations relying on affected Mozilla applications as part of their computing infrastructure. The remote exploitability means that attackers can leverage this weakness without requiring local system access, making it particularly dangerous in enterprise environments where users may encounter malicious content through web browsing or email interactions. The potential for denial of service attacks can disrupt business operations by causing application crashes and forcing users to restart affected applications. Additionally, the arbitrary code execution capability transforms this vulnerability into a serious threat that could enable attackers to establish persistent footholds within target networks, potentially leading to data breaches or further compromise of system resources.
Organizations should prioritize immediate patching of affected systems to address this vulnerability, as the exploitation window remains open for users running vulnerable versions of Mozilla Firefox, SeaMonkey, and Thunderbird. Security teams should implement network monitoring to detect potential exploitation attempts and consider deploying additional protective measures such as web application firewalls or content filtering solutions. The vulnerability's impact on multiple products within the Mozilla ecosystem necessitates comprehensive inventory checks to identify all affected applications and systems. Incident response procedures should include specific protocols for handling potential exploitation attempts, with particular attention to memory corruption patterns that may indicate successful exploitation of this JavaScript engine vulnerability. Organizations should also consider implementing browser hardening measures and user education programs to reduce the risk of successful exploitation through social engineering or phishing attacks that deliver malicious JavaScript content.