CVE-2009-4246 in RealPlayer
Summary
by MITRE
Stack-based buffer overflow in RealNetworks RealPlayer 10, RealPlayer 10.5 6.0.12.1040 through 6.0.12.1741, RealPlayer 11 11.0.0 through 11.0.4, RealPlayer Enterprise, Mac RealPlayer 10 and 10.1, Linux RealPlayer 10, and Helix Player 10.x allows user-assisted remote attackers to execute arbitrary code via a malformed .RJS skin file that contains a web.xmb file with crafted length values.
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Analysis
by VulDB Data Team • 04/29/2026
The vulnerability described in CVE-2009-4246 represents a critical stack-based buffer overflow affecting multiple versions of RealNetworks RealPlayer software across different platforms including Windows, Mac, and Linux operating systems. This flaw exists within the handling of .RJS skin files that contain web.xmb components, making it particularly dangerous as it can be exploited through user-assisted remote attacks. The vulnerability specifically impacts RealPlayer versions 10, 10.5, 11, and the Enterprise and Helix Player variants, with the affected range spanning from 6.0.12.1040 through 6.0.12.1741 for RealPlayer 10.0, and 11.0.0 through 11.0.4 for RealPlayer 11.0. The attack vector requires a maliciously crafted .RJS file that contains a web.xmb file with deliberately manipulated length values, which when processed by the vulnerable software triggers the buffer overflow condition.
The technical implementation of this vulnerability stems from improper input validation within the RealPlayer application's parsing mechanism for skin files. When the software encounters a malformed .RJS file containing a web.xmb component with crafted length values, it fails to properly bounds-check the data before copying it into a fixed-size stack buffer. This oversight creates a condition where attacker-controlled data can overflow the allocated buffer space, potentially overwriting adjacent memory locations including return addresses and control data. The CWE-121 classification applies here as this represents a classic stack-based buffer overflow where insufficient bounds checking allows for memory corruption. The vulnerability's exploitation requires user interaction since the malicious file must be opened or processed by the victim's system, but once executed, it provides remote code execution capabilities. The attack scenario typically involves an attacker hosting a malicious .RJS file on a web server or sending it via email, where a user's RealPlayer application processes the file and triggers the overflow.
The operational impact of CVE-2009-4246 extends beyond simple privilege escalation or system compromise, as it enables full remote code execution capabilities within the context of the user running RealPlayer. This vulnerability directly maps to the ATT&CK technique T1203 - Exploitation for Client Execution, where adversaries leverage software vulnerabilities to execute malicious code on target systems. The affected platforms include various versions of RealPlayer across different operating systems, making this vulnerability particularly widespread and difficult to contain. Attackers can leverage this vulnerability to install backdoors, steal sensitive information, or establish persistent access to compromised systems. The vulnerability's exploitation requires minimal prerequisites beyond having the vulnerable RealPlayer software installed, making it a particularly attractive target for threat actors. The affected software versions represent widely deployed media players, which increases the potential attack surface significantly. Organizations using these older versions of RealPlayer face substantial risk as the vulnerability has been known for years and lacks proper patching mechanisms in legacy deployments.
Mitigation strategies for CVE-2009-4246 must address both immediate remediation and long-term security posture improvements. The primary and most effective mitigation involves immediate patching of all affected RealPlayer versions, as RealNetworks released security updates to address this specific vulnerability. System administrators should disable or remove RealPlayer installations when not actively required, particularly in enterprise environments where the software is not essential for business operations. Network-based protections should include blocking access to potentially malicious .RJS files through web application firewalls and content filtering solutions. File type restrictions and sandboxing mechanisms can help prevent automatic execution of potentially malicious skin files. The vulnerability's nature makes it particularly susceptible to defensive measures such as DEP (Data Execution Prevention) and ASLR (Address Space Layout Randomization) implementations, though these protections are not foolproof against sophisticated attacks. Organizations should also implement regular software inventory tracking to identify legacy RealPlayer installations and ensure they are updated or decommissioned. Additionally, user education regarding the risks of opening unknown or untrusted media files remains crucial, as the vulnerability requires user-assisted execution to be effective. The ATT&CK framework suggests implementing process monitoring and anomaly detection to identify unusual file processing activities that might indicate exploitation attempts. Security teams should also consider network segmentation to limit the potential impact of successful exploitation, ensuring that compromised systems cannot easily access critical network resources.