CVE-2009-1104 in JRE
Summary
by MITRE
The Java Plug-in in Java SE Development Kit (JDK) and Java Runtime Environment (JRE) 5.0 Update 17 and earlier; 6 Update 12 and earlier; and 1.4.2_19 and earlier does not prevent Javascript that is loaded from the localhost from connecting to other ports on the system, which allows user-assisted attackers to bypass intended access restrictions via LiveConnect, aka CR 6724331. NOTE: this vulnerability can be leveraged with separate cross-site scripting (XSS) vulnerabilities for remote attack vectors.
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Analysis
by VulDB Data Team • 08/09/2021
The vulnerability described in CVE-2009-1104 represents a critical security flaw in the Java Plug-in component of Java SE Development Kit and Runtime Environment versions prior to the specified updates. This issue specifically affects Java 5.0 Update 17, Java 6 Update 12, and Java 1.4.2_19 releases, creating a significant bypass of intended network access controls within the Java sandbox environment. The flaw enables malicious javascript code executed from localhost to establish connections to arbitrary ports on the target system, effectively undermining the security boundaries that Java's security model is designed to maintain.
The technical implementation of this vulnerability stems from improper handling of LiveConnect functionality within the Java Plug-in. LiveConnect is a mechanism that allows javascript running in web browsers to communicate with java applets and vice versa. In vulnerable versions, the Java Plug-in fails to properly enforce security restrictions when javascript code originating from localhost attempts to establish network connections through LiveConnect. This creates a pathway where javascript code can bypass the standard security policies that normally prevent network access from applets and browser-based code, allowing direct system port connections without proper authorization checks.
The operational impact of this vulnerability is particularly concerning as it can be exploited through user-assisted attacks, meaning that an attacker would need to convince a user to execute malicious javascript code, but once executed, the vulnerability allows for significant system compromise. The vulnerability becomes even more dangerous when combined with cross-site scripting attacks, as the attacker can leverage XSS to deliver the malicious javascript payload to a victim's browser. This combination creates a remote attack vector where an attacker can potentially gain unauthorized access to system services, perform port scanning, or even establish reverse connections to command and control servers, effectively turning the victim's system into a potential attack platform.
This vulnerability maps directly to CWE-284, which addresses improper access control issues, and aligns with ATT&CK technique T1059.007 for JavaScript execution and T1068 for local privilege escalation. The flaw represents a classic sandbox escape mechanism where browser-based code can bypass the security boundaries that should separate trusted and untrusted execution environments. Organizations should immediately implement patch management procedures to upgrade to affected Java versions, disable Java plugin execution in browsers when not required, and implement network monitoring to detect unauthorized port scanning or connection attempts from localhost. Additionally, security awareness training should emphasize the dangers of executing untrusted javascript code and the importance of keeping Java installations updated to prevent exploitation of such vulnerabilities that could lead to complete system compromise.