CVE-2009-0304 in OpenSolaris
Summary
by MITRE
The kernel in Sun Solaris 10 and 11 snv_101b, and OpenSolaris before snv_108, allows remote attackers to cause a denial of service (system crash) via a crafted IPv6 packet, related to an "insufficient validation security vulnerability," as demonstrated by SunOSipv6.c.
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Analysis
by VulDB Data Team • 05/16/2025
The vulnerability identified as CVE-2009-0304 represents a critical denial of service flaw affecting the kernel implementations of Sun Solaris 10 and 11 snv_101b, along with OpenSolaris versions prior to snv_108. This security issue stems from inadequate validation mechanisms within the IPv6 processing code, specifically within the SunOSipv6.c module that handles IPv6 packet processing. The flaw demonstrates a clear weakness in the kernel's network stack validation procedures, where malformed or crafted IPv6 packets can trigger system instability and complete system crashes. This vulnerability operates at the kernel level, meaning that successful exploitation can result in complete system compromise without requiring authentication or elevated privileges, making it particularly dangerous in networked environments where IPv6 traffic is processed.
The technical root cause of this vulnerability lies in insufficient input validation within the IPv6 packet handling routines of the Solaris kernel. When the system receives a specially crafted IPv6 packet, the kernel fails to properly validate the packet structure, length, or header contents before processing. This validation failure creates a pathway for attackers to inject malformed data that causes memory corruption or improper state handling within kernel memory spaces. The vulnerability specifically affects the IPv6 implementation in Sun's operating systems, where the kernel's network processing code does not adequately check for valid packet boundaries or proper header field values. This type of vulnerability is classified under CWE-20, which describes "Improper Input Validation," and represents a classic example of how insufficient validation can lead to system instability and denial of service conditions.
The operational impact of this vulnerability extends beyond simple system crashes, as it can be exploited remotely without requiring any authentication credentials or special privileges. An attacker positioned on the network can send a single malicious IPv6 packet to a target system running vulnerable Solaris versions, causing immediate system failure and requiring manual intervention to restore normal operations. This makes the vulnerability particularly attractive to attackers seeking to disrupt services or cause availability issues in targeted environments. The impact is severe because Solaris systems are commonly used in enterprise environments, web servers, and network infrastructure, meaning that successful exploitation can affect critical business operations and potentially lead to extended downtime. The vulnerability's remote exploitability means that attackers do not need physical access or network proximity to the target system, making it a significant threat in any network environment where IPv6 traffic is processed.
Mitigation strategies for this vulnerability require immediate patching of affected Solaris systems with the appropriate security updates provided by Sun Microsystems. Organizations should prioritize updating their Solaris installations to versions that contain fixes for the IPv6 validation issues in the SunOSipv6.c module. Network administrators should also consider implementing network segmentation and access controls to limit exposure to potentially malicious IPv6 traffic, although this approach provides only partial protection. The vulnerability aligns with ATT&CK technique T1499.001, which covers "Network Denial of Service," and represents a classic example of how kernel-level flaws can be exploited to cause system-wide availability issues. Additionally, monitoring network traffic for unusual IPv6 packet patterns and implementing intrusion detection systems can help identify potential exploitation attempts. System administrators should also consider disabling IPv6 functionality on systems where it is not required, as this provides an additional layer of defense against exploitation attempts targeting this specific vulnerability.