CVE-2010-3962 is a high-severity use-after-free vulnerability in Microsoft Internet Explorer versions 6, 7, and 8. This vulnerability allows remote attackers to execute arbitrary code via specific vectors related to Cascading Style Sheets (CSS) token sequences and the clip attribute. The issue, often referred to as an "invalid flag reference" or "Uninitialized Memory Corruption Vulnerability," was actively exploited in the wild in November 2010. The CVSS 3.1 score for this vulnerability is 8.1, indicating a high severity level, which necessitates immediate attention from organizations.
Organizations face significant risks due to this vulnerability. Attackers may leverage this flaw to gain unauthorized access and execute arbitrary code on affected systems, potentially leading to data breaches and loss of sensitive information. Given the nature of the vulnerability and its historical exploitation, organizations should prioritize patching immediately to mitigate these risks.
The urgency for defenders is heightened due to the vulnerability's inclusion in the Known Exploited Vulnerabilities (KEV) catalog as of October 6, 2025. The recommended action is to apply mitigations as per vendor instructions and to discontinue the use of affected products if no mitigations are available. This emphasizes the critical nature of addressing this vulnerability promptly.
Organizations utilizing Microsoft Internet Explorer must recognize the potential impact of this vulnerability and take necessary actions to secure their systems against possible exploitation.
Vulnerability Details
The official CVE description identifies this as a use-after-free vulnerability, which occurs when a program attempts to use memory after it has been freed. This specific vulnerability affects Microsoft Internet Explorer versions 6, 7, and 8. The CVSS score of 8.1 signifies a high severity level due to the potential for remote code execution. The affected product is Microsoft Internet Explorer, and the vulnerability was published on November 5, 2010. It is classified under CWE-416, which pertains to use-after-free vulnerabilities.
Technical Analysis
The root cause of CVE-2010-3962 lies in the mishandling of memory in Internet Explorer, specifically related to CSS token sequences and the clip attribute. The attack vector for this vulnerability is network-based, meaning that it can be exploited remotely without the need for physical access to the vulnerable system. The attack complexity is classified as high, indicating that successful exploitation may require specific conditions or a well-crafted attack. Importantly, no user interaction is required for exploitation, which increases the risk as users may not be aware of the threat.
The impacts of successful exploitation are severe, affecting confidentiality, integrity, and availability, all rated as high. This means that attackers can not only gain access to sensitive information but can also alter data and disrupt services, leading to significant operational downtime.
Risk & Impact Analysis
The real-world deployment risk associated with CVE-2010-3962 is substantial. Organizations using Microsoft Internet Explorer are at risk of unauthorized access and potential data breaches. The blast radius of this vulnerability includes any organization that has not yet upgraded from affected versions of Internet Explorer, which may still be in use in legacy systems.
The urgency assessment indicates that organizations should prioritize addressing this vulnerability due to its high CVSS score and its presence in the KEV catalog. Failure to act could lead to severe consequences, including financial losses, reputational damage, and regulatory penalties.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | Yes |
Public PoC | Yes |
Actively Exploited | Yes |
Ransomware Use | No |
Affected Versions
The vulnerability affects Microsoft Internet Explorer versions 6, 7, and 8. All versions prior to the vendor patch are considered vulnerable. Organizations should upgrade to the latest version to ensure security.
Mitigation & Remediation
Organizations must apply the latest security patches provided by Microsoft to mitigate this vulnerability. The recommended action is to upgrade to supported versions of Internet Explorer or discontinue using unsupported versions. For further information, organizations can refer to the penetration testing services to validate the effectiveness of the mitigations implemented.
Detection Guidance
To detect potential exploitation of CVE-2010-3962, organizations should monitor for unusual network traffic patterns indicative of exploitation attempts, such as unexpected CSS token sequences. Additionally, logging and analyzing error messages related to Internet Explorer can help identify potential abuse of the vulnerability.
AppSecure Threat Intelligence Insight
CVE-2010-3962 highlights the importance of maintaining updated software to protect against vulnerabilities. The long-term significance of this vulnerability lies in its representation of outdated technology that continues to pose risks in modern environments. Organizations should learn from this incident and ensure that legacy systems are either updated or decommissioned to reduce the attack surface.
Security teams should prioritize vulnerability management programs that focus on identifying and mitigating risks associated with legacy software. For more information on effective vulnerability management, organizations can refer to the vulnerability management program design guidelines.
Furthermore, organizations should consider engaging in proactive security assessments, such as penetration testing methodologies, to identify and remediate similar vulnerabilities in their systems.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
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