CVE-2015-4495 is a high-severity vulnerability affecting Mozilla Firefox versions prior to 39.0.3, Firefox ESR 38.x before 38.1.1, and Firefox OS before 2.2. This vulnerability allows remote attackers to bypass the Same Origin Policy, which can lead to unauthorized access to arbitrary files or privilege escalation through crafted JavaScript code. The risk to organizations includes potential unauthorized access to sensitive information, as evidenced by its exploitation in the wild in August 2015.
The vulnerability has a CVSS score of 8.8, indicating a high severity level. This score reflects its potential impact on confidentiality, integrity, and availability, all rated as high. Given the nature of the attack vector—over the network—and the relatively low attack complexity, organizations must prioritize patching to mitigate risks associated with this vulnerability.
As of now, the vulnerability is known to be actively exploited, and a public exploit is available. Organizations should take immediate action to apply relevant patches to their systems. Mozilla has provided updates to address this issue, and it is critical for users to ensure they are using the latest version of Firefox.
Organizations should prioritize patching immediately.
Vulnerability Details
The PDF reader in Mozilla Firefox allows attackers to exploit vulnerabilities through a crafted JavaScript code that interacts with a native setter, effectively bypassing the Same Origin Policy. This type of vulnerability is classified under CWE-346. The CVSS score of 8.8 indicates a high severity, and the vulnerability is specifically linked to the ability of attackers to read arbitrary files or gain elevated privileges.
Technical Analysis
The root cause of CVE-2015-4495 lies in the improper handling of JavaScript within the PDF reader component of Firefox, which allows for the bypass of security policies. The attack vector is network-based, requiring low complexity, and no privileges are required to exploit it. However, user interaction is necessary, meaning that an attacker would need to trick a user into opening a malicious PDF file. The impact on confidentiality, integrity, and availability is high, as unauthorized access to files could lead to significant data breaches.
Risk & Impact Analysis
The deployment of Mozilla Firefox in various organizational environments increases the risk associated with this vulnerability. Given the high CVSS score, organizations must evaluate their exposure and potential blast radius. Attackers may leverage this vulnerability to access sensitive information, making it essential for organizations to understand the implications of unpatched systems. The urgency is critical, given its active exploitation status.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | Yes |
Public PoC | Yes |
Actively Exploited | Yes |
Ransomware Use | No |
Affected Versions
Affected versions include Mozilla Firefox prior to 39.0.3, Firefox ESR versions prior to 38.1.1, and Firefox OS prior to 2.2. Organizations using these versions are at risk and should apply patches as soon as possible.
Mitigation & Remediation
Mozilla has released updates to address this vulnerability. Organizations should apply these updates as per vendor instructions. If immediate patching is not feasible, consider implementing network controls to limit exposure and monitor for any unusual activity related to the affected components. Additionally, organizations may benefit from utilizing penetration testing to identify vulnerabilities that may arise due to unpatched systems.
Detection Guidance
To detect potential exploitation of this vulnerability, organizations should monitor logs for unusual access patterns or attempts to read local files via the PDF reader. Behavioral anomalies in user interactions with PDFs should also be tracked. Network signatures that identify known exploit attempts can further enhance detection capabilities.
AppSecure Threat Intelligence Insight
CVE-2015-4495 serves as a reminder of the importance of robust security measures in software development. The exploitation of vulnerabilities in widely used applications like Firefox highlights the need for ongoing vigilance. Security teams should consider integrating lessons learned from this incident into their vulnerability management practices. Regular reviews of security configurations and proactive testing can mitigate similar risks in the future. Organizations may want to explore resources on penetration testing methodology and vulnerability management programs to strengthen their defenses.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
.webp)